Dissertations / Theses on the topic 'Lanthanide metals'
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Dyer, Hellen Elizabeth. "New lanthanide complexes as polymerisation catalysts." Thesis, University of Oxford, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.560913.
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This Thesis describes the synthesis and characterisation of a series ofbisphenolate supported samarium borohydride, amide and zwitterionic rare earth complexes and their ability to effect the ring opening polymerisation (ROP) of cyclic esters and methylmethacrylate (MMA). Chapter 1 introduces ROP from both an industrial and an academic perspective and describes in detail the research in this area, with emphasis on rare earth initiators. The lanthanide elements and the bisphenolate ligand are also introduced. Chapter 2 describes the synthesis and characterisation ofbisphenolate supported samarium borohydride and silylamide complexes. Chapter 3 describes the ability of a selection of samarium borohydride and amide complexes to effect the ROP of the cyclic esters s-caprolactone (f-CL) and rac- lactide (rac-LA). Emphasis is placed on the effect that the nature of the bisphenolate pendant arm and the initiating moiety has on the polymerisation process. Chapter 4 describes the synthesis and characterisation of rare earth zwitterionic complexes and the ability ofa range of these complexes to effect the ROP of s-Cl. and rac-lactide. Mechanistic aspects ofthe ROP process will be discussed, as will the ability of these complexes to yield amide functionalised poly(rac-LA). Chapter 5 describes the ability ofbisphenolate samarium borohydride complexes to initiate the polymerisation of MMA. The experimental work conducted as part of this study is further supported computationally by calculations at the DFT level, both aspects will be described. Aspects concerning the synthesis and characterisation of the related borohydride derivative [Sm(N2siMe3NNPY)(BH4)2Li]oo will also be emphasised. Chapter 6 contains full experimental and characterising data for all 0 f the new compounds reported in this Thesis. Appendices A- T contain tables of selected crystallographic data for all new crystallographically characterised complexes described in this Thesis (partially on CD).
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Dai, Lixiong. "Structural modifications to optimise lanthanide luminescence." HKBU Institutional Repository, 2017. http://repository.hkbu.edu.hk/etd_oa/403.
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Luminescent lanthanide coordination complexes have attracted significant attention due to their unique optical properties. The poor absorption of a lanthanide ion can be resolved by so-called antenna effect and improve the intensity of its luminescence. Three bidentate chromophores: phosphate-pyridine chromophore, 1,2-Hydroxy pyridone (1,2-HOPO) and 2-thenoyltrifluoroacetone (TTA), functioned as both chelator and sensitizer, their energy levels are well matched with the excited state energy levels of the Eu(III) and Sm(III).. To get highly luminescent and stable lanthanide complex, we designed and synthesized various Eu(III) complexes with different backbones to compare different parameters that will affect the sensitizing efficiency of the chromophores, such as rigidity, geometry and coordination saturation.. In chapter two we combined the phosphate-pyridine chromophore with the well-studied cyclen-based chelator to fulfil the requirement of high stability and brightness. We designed a nine-coordinate europium(III) complex as platform, through coupling reactions to realise fast screen of the chromophores energy transfer efficiency.. Chapter three focuses on the structure modifications based on the chromophore of 1,2-HOPO, different chelators and backbones were compared, a europium complex EuL4 with the highest quantum yield with this chromophore was obtained and it could goes into cells and localized on lysosome very fast. Two-phonon in vitro imaging was done which showed its high potential bioapplications.. Chapter four focuses on the structure modification based on the chromophore of TTA. Different backbone directly determined the europium complexes saturation number and sensitization efficiency, therefore, their quantum yields.
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Jin, Geng Bang. "Synthesis and characterization of new Lanthanide chalcogenides." Auburn, Ala., 2007. http://repo.lib.auburn.edu/07M%20Dissertations/JIN_GENGBANG_37.pdf.
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Isler, Jeremy Payton. "Interactions of Lanthanides and Liquid Alkali Metals for "Liquid-Like" Lanthanide Transport in U-Zr Fuel." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1492607350430645.
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Munro, Keith Alistair. "High-pressure high-temperature behaviour of the lanthanide metals." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/28881.
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The high-pressure behaviour of the lanthanide series of metals has been the subject of study since the work of Percy Bridgman in the 1940s. Differences in said behaviour between the different lanthanide metals are attributed to the increasing occupation of the 4f electron shell as Z increases. Upon compression, or as Z decreases, the trivalent lanthanides (La to Lu, excluding Eu and Yb) undergo a common phase transformation sequence through various close packed structures: hcp → Sm-type (the structure adopted by samarium at ambient conditions) → dhcp → fcc → distorted fcc (d-fcc). Upon further compression, the lanthanide metals experience a first order transition to a "volume collapsed" phase. Many studies have focused on the low-Z members of the series, since the various phase transitions occur at much lower pressure where it is comparatively easy to collect high quality data. By contrast, the other members of the series have received comparability little attention, and there are even fewer reports of the structural behaviour of the lanthanide metals at high pressure and high temperature. This thesis contains the results of angle-dispersive x-ray powder diffraction experiments at high pressure and high temperature of the various members of the lanthanide metals. Ce has been the subject of many previous studies, but a systematic x-ray diffraction study of the fcc/d-fcc phase boundary has never been attempted. Furthermore, the location in P-T space of the high temperature fcc/bct/d-fcc triple point has only been inferred, due to the lack of data on the fcc/bct phase boundary at high temperature. The high-pressure high-temperature phase diagram of Ce is presented and discussed. La is unique amongst the lanthanide metals due to its empty 4f shell at ambient conditions. Despite this, La undergoes the common lanthanide transformation sequence up to the d-fcc phase, after which it undergoes a re-entrant transition back to the fcc phase at 60 GPa. The diffraction peaks of d-fcc La are shown in this thesis to undergo changes in intensity upon compression, indicating a transformation to the oI 16 structure found in Pr. La is one of the few elements whose behaviour has been unknown above 100 GPa, and results of La's structural behaviour upon compression to 280 GPa are presented and discussed. At 76 GPa, La begins a transition from the fcc phase to a new phase with the bct structure. Finally, the d-fcc→fcc re-entrant phase transition has been determined at various temperatures, and the d-fcc stability region has been mapped out. Finally, x-ray diffraction experiments were performed on Gd up to 100 GPa and ~700 K, to determine the structure of the d-fcc phase and the "volume collapsed" phase. While d-fcc Gd does not undergo pressure-induced changes similar to its low Z brethren, the d-fcc Gd remains stable up to 41 GPa at 700 K, putting a constraint on the d-fcc stability region. The data collected on Gd's "volume collapsed" phase cannot be fitted to the currently accepted mC4 structure. This has implications for our understanding of the lanthanide series as a whole, since most of of the heavier members, and some of the lighter lanthanides, are reported to adopt the mC4 structure.
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Li, King Fai. "Photoluminescent mechanism of trivalent lanthanide organic complexes." HKBU Institutional Repository, 2002. https://repository.hkbu.edu.hk/etd_ra/364.
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Coetzee, Louis-Charl Cloete. "A study of lanthanide complexes with di-2-pyridyl ligands." Thesis, Nelson Mandela Metropolitan University, 2016. http://hdl.handle.net/10948/4731.
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The ligands di(2-pyridyl) ketone (DPK) and cis-1,2 di(2-pyridyl) ethylene (DPE) are N,N,Odonor ligands that can undergo nucleophilic addition and become more flexible for coordination. The reaction between the lanthanide thiocyanate salt and DPK gave rise to seven novel complexes of the general formula [Ln(NCS)3(DPKOH)3], where Ln = La, Ce, Nd, Eu, Tb, Dy and Ho. 1H NMR spectroscopy verified that the ligand underwent nucleophilic addition upon coordination. This was further confirmed using UV-Vis spectroscopy which showed a shift in the absorption bands due to conjugation of electrons within the pyridyl ring upon coordination. UV-Vis spectroscopy was also utilised to test the covalent character of the neodymium and holmium complexes. X-ray diffraction and IR spectroscopy showed that three DPK ligands coordinated bidentately through a pyridinic nitrogen and a hydroxyl oxygen, while three isothiocyanato molecules completed the coordination environment around each metal. Furthermore, X-ray diffraction also revealed that these complexes are isostructural, ninecoordinate and the polyhedron which encloses each ion is of trigonal tricapped prismatic shape with D3h symmetry. Micro-analysis on all the complexes, except lanthanum and holmium confirmed the molecular formulae produced from the crystallographic data of each complex. The reaction between the lanthanide thiocyanate salt and DPE produced poor quality crystals which could not be detected by X-ray diffraction. The lanthanide salts used for this reaction were lanthanum, neodymium, europium, dysprosium and holmium. Upon coordination, conductivity measurements detected the presence of lanthanide ions in each solution. 1H NMR and IR spectroscopic studies showed that the ethylenic moiety of DPE underwent nucleophilic addition upon coordination. UV-Vis spectroscopy further confirmed nucleophilic addition upon coordination due to shifts in absorption bands. IR spectroscopy verified the possibility of a bidentate coordination to each metal through a pyridinic nitrogen and a hydroxyl oxygen as well as a monodentate coordination through isothiocyanato ligands. A micro-analysis on all the complexes provided the molecular formulae that can best fit each complex. The effect of the solvent molecules on the bonding parameters of the lanthanum complex was investigated. An analysis of the results produced from crystallographic data revealed the presence of intermolecular forces which interacted and stabilised the complex.
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Zhu, Xunjin. "Synthesis, characterization and photoluminescence of lanthanide porphyrinate complexes." HKBU Institutional Repository, 2006. http://repository.hkbu.edu.hk/etd_ra/695.
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Wong, Ka-Leung. "Synthesis, characterization, and photophysical studies of organic-lanthanide complexes." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36875351.
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Sultan, Muhammad [Verfasser]. "Ultrafast magnetization dynamics of lanthanide metals and alloys / Muhammad Sultan." Berlin : Freie Universität Berlin, 2012. http://d-nb.info/102715171X/34.
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Jayasundera, Anil. "Solvothermal chemistry of luminescent lanthanide fluorides." Thesis, University of St Andrews, 2009. http://hdl.handle.net/10023/2125.
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Exploration of novel lanthanide fluoride framework materials in inorganic-organic hybrid systems under solvothermal conditions towards development of new luminescent materials is discussed. X-ray single crystal and powder diffraction methods have been used as crystallographic characterisation techniques. Determination and study of luminescence properties for selected hybrid materials has also been carried out. The first organically templated luminescent lanthanide fluoride framework, [C₂N₂H₁₀]₀.₅ [Ln₂F₇] (Ln= Nd, Tb, Dy, Ho, Er, Yb and Lu), has been synthesised and characterised. This structure type consists of a three-dimensional yttrium fluoride framework incorporating two similar, but crystallographically distinct, yttrium sites. Photoluminescence studies of [C₂N₂H₁₀]₀.₅ [Y₂F₇]: Ln³⁺ (Ln³⁺ = Gd³⁺, Eu³⁺ and Tb³⁺) have been explored and characteristic luminescence emissions are reported. An inorganic-organic hybrid indium fluoride and its scandium fluoride analogue, [C₄H₁₄N₂][MF₅](M=In and Sc) is reported. The structure consists of infinite trans vertex sharing (InF₅)[subscript(∞)] chains, which are linked via H-bonded organic moieties. The scandium and fluorine local environments of [C₄H₁₄N₂][ScF₅] are characterised by ¹⁹F, and ⁴⁵Sc solid-state MAS NMR spectroscopies. A single scandium site has been confirmed by ⁴⁵Sc MAS NMR. ¹⁹F MAS NMR clearly differentiates between bridging and terminal fluorine. The photoluminescence properties of these complexes, [C₄H₁₄N₂][In[subscript(1-x)] Ln[subscript(x)]F₅] (Ln=Tb and/or Eu), have been explored. The optimum composition for Eu³⁺ doped samples occurs at x = 0.05 Eu³⁺ and the “asymmetry ratio” of R = I₅₉₀/I₆₁₅ ( ⁵D₀ → ⁷F₂ and ⁵D₀ → ⁷F₁) gives a clear picture of the sensitivity for crystal field of the compound. For x = 0.08 Tb³⁺, a strong down-conversion fluorescence corresponding to ⁵D₄ → ⁷F₅ (green at 543.5 nm) occurs. In addition, a Tb³⁺/Eu³⁺ co-doped sample exhibits a combination of green (Tb³⁺) and orange (Eu³⁺) luminescence, with Tb³⁺ enhancing the emission of Eu³⁺ in this host. Exploration of novel indium, aluminium, and zirconium fluoride crystal structures with potential luminescent properties has also been undertaken. A chiolite-like phase K₅In₃F₁₄ (space group P4/mnc) has been synthesised. No phase transition occurs over the temperature range 113K< T< 293 K, as has been seen in other chiolite-like structures. An organically templated indium fluoride, [NH₄]₃[C₆H₂₁N₄]₂[In₄F₂₁] has been prepared; this features the trimeric unit [In₃F₁₅]³⁻ which appears to be the first of its type in a metal fluoride. A new hybrid fluoride, Sr[N₂C₂H₁₀]₂[Al₂F₁₂].H₂O has been synthesised. Because the ionic radius of Eu²⁺ is similar to that of Sr ²⁺ this may be a potential host for blue luminescent Eu²⁺. The new material KZrF₅.H₂O shows pentagonal-bipyramidal geometry of Zr⁴⁺ with a polar space group, Pb2₁m, which may potentially have ferroelectric properties.
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Wong, Ka-Leung, and 黃嘉良. "Synthesis, characterization, and photophysical studies of organic-lanthanide complexes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B36875351.
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Madanhire, Tatenda. "Synthesis and characterisation of lanthanide complexes with nitrogen- and oxygen-donor ligands." Thesis, Nelson Mandela Metropolitan University, 2016. http://hdl.handle.net/10948/13127.
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The reactions of Ln(NO3)3∙6H2O (Ln = Pr, Nd or Er) with the potentially tridentate O,N,O chelating ligand 2,6-pyridinedimethanol (H2pydm) were investigated, and complexes with the formula, [Ln(H2pydm)2(NO3)2](NO3) (Ln = Pr or Nd) and [Er(H2pydm)3](NO3)3 were isolated. The ten-coordinate Pr(III) and Nd(III) compounds crystallise in the triclinic space group P-1 while the nine-coordinate Er(III) complex crystallises in the monoclinic system (P21/n). The reaction of PrCl3∙6H2O with H2pydm yielded the compound, [Pr(H2pydm)3](Cl)3, that crystallises in the monoclinic system, space group P21/c with α = 90, β = 98.680(1) and γ = 90°. The nine-coordinate Pr(III) ion is bound to three H2pydm ligands, with bond distances Pr-O 2.455(2)-2.478(2) Å and Pr-N 2.6355(19)-2.64(2) Å. X-ray crystal structures of all the H2pydm complexes reveal that the ligand coordinates tridentately, via the pyridyl nitrogen atom and the two hydroxyl oxygen atoms. The electronic absorption spectra of complexes show 4f-4f transitions. Rare-earth complexes, [Ln(H2L1)2(NO3)3] [Ln = Gd, Ho or Nd], were also prepared from a Schiff base. The X-ray single-crystal diffraction studies and SHAPE analyses of the Gd(III) and Ho(III) complexes shows that the complexes are ten-coordinate and exhibit distorted tetradecahedron geometries. With proton migration occurring from the phenol group to the imine function, complexation of the lanthanides to the ligand gives the ligand a zwitterionic phenoxo-iminium form. A phenolate oxygen-bridged dinuclear complex, [Ce2(H2L1)(ovan)3(NO3)3], has been obtained by reacting Ce(NO3)3∙6H2O with an o-vanillin derived Schiff base ligand, 2-((E)-(1-hydroxy-2-methylpropan-2-ylimino)methyl)-6-methoxyphenol (H2L1). Hydrolysis of the Schiff base occurred to yield o-vanillin, which bridged two cerium atoms with the Ce∙∙∙Ce distance equal to 3.823 Å. The Ce(III) ions are both tencoordinate, but have different coordination environments, showing tetradecahedron and staggered dodecahedron geometries, respectively. The reaction of salicylaldehyde-N(4)-diethylthiosemicarbazone (H2L2) in the presence of hydrated Ln(III) nitrates led to the isolation of two novel compounds: (E)-2[(ortho-hydroxy)benzylidene]-2-(thiomethyl)-thionohydrazide (1) and bis[2,3-diaza4-(2-hydroxyphenyl)-1-thiomethyl-buta-1,3-diene]disulfide. The latter is a dimer of the former. For this asymmetric Schiff base, 1 and the symmetric disulfide, classical hydrogen bonds of the O–H∙∙∙N as well as N–H∙∙∙S (for 1) type are apparent next to C–H∙∙∙O contacts. 4-(4-Bromophenyl)-1-(propan-2-ylidene)thiosemicarbazide was also prepared upon reacting 4-(4-bromophenyl)-3-thiosemicarbazide with acetone in the presence of ethanol and La(NO3)3∙6H2O. The C=S bond length was found to be 1.6686(16) Å which is in good agreement with other thioketones whose metrical parameters have been deposited with the Cambridge Structural Database. Classical hydrogen bonds of the N–H∙∙∙N and the N–H∙∙∙Br type are observed next to C–H∙∙∙S contacts. All synthesised compounds were characterised by microanalyses, single-crystal X-ray diffraction (except for [Nd(H2L1)2(NO3)3]), 1H NMR and IR spectroscopy.
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Zhou, Yan. "Synthesis, photophysical and biological studies of lanthanide complexes for photodynamic therapy." HKBU Institutional Repository, 2017. https://repository.hkbu.edu.hk/etd_oa/467.
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1.2\xPrior to the PDT, we have also synthesized a series of water-soluble homoleptic lanthanides (Ln3+ = Gd, Er, and Yb) sandwich (DD) di-PEGylated porphyrin complexes. The Yb complex (YbDD) has shown the same NIR emission quantum yield as the highest record Yb complex in the literature (Yb-RhB), yet, the emission intensity is double compared to the Yb-N. This implies a new thinking about the quantity measurement for biological imaging. The brightness might be the prime factor for the development of luminescence in vitro/in vivo imaging agent rather than the emission quantum yield.
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Bao, Guochen. "The study of photophysical properties of organic-lanthanide hybrid materials and their applications." HKBU Institutional Repository, 2020. https://repository.hkbu.edu.hk/etd_oa/773.
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Designing hybrid materials allows leveraging the properties of different material systems to achieve novel functions. Significant progress has been made in recent years to exploit the physicochemical properties of a new generation of hybrid materials for emerging biomedical applications. In Chapter 1, I review the recent advances in the field of dye-lanthanide hybrid materials, centring on the interface between organic dyes and inorganic lanthanide materials and investigating their photophysical and photochemical properties. Five representative dye-lanthanide hybrid material systems including lanthanide complex, dye-sensitised downshifting nanoparticles (DSNPs), dye-sensitised downconversion nanoparticles (DCNPs), dye-sensitised upconversion nanoparticles (UCNPs), and UCNPs-dye energy transfer systems have been thoroughly discussed. We highlight the key applications of dye-lanthanide hybrid materials in bioimaging, sensing, drug delivery, therapy, and cellular activity studies. In Chapter 2, I design and synthesize an ytterbium complex-based sensor for the detection of Hg2+ ions. The water-soluble ytterbium complex exhibits reversible off−on visible and NIR emission upon the binding with mercury ion. The fast response and 150 nM sensitivity of Hg2+ detection are based upon FRET and the lanthanide antenna effect. The reversible Hg2+ detection can be performed in vitro, and the binding mechanism is studied by NMR employing the motif structure in a La complex and by DFT calculations. In Chapter 3, I report a pair of stoichiometric terbium-europium dyads as molecular thermometers and study their energy transfer properties. A strategy for synthesizing hetero-dinuclear complexes that contain chemically similar lanthanides is developed. By this strategy, a pair of thermosensitive dinuclear complexes, cycTb-phEu and cycEu-phTb, was synthesized. Their structures were geometrically optimized with an internuclear distance of approximately 10.6 Å. The dinuclear complexes have sensitive temperature-dependent luminescent intensity ratios of europium and terbium emission, and temporal dimension responses over a wide temperature range (50 - 298 K and 10 - 200 K, respectively). This indicates that both dinuclear complexes are excellent self-referencing thermometers. In Chapter 4, I investigate spectral structure and intensity changes of a pair of dinuclear complexes with a europium ion on cyclen site and a lanthanum ion on phen site or vice verses (cycEu-phLa and cycLa-phEu). Though they have the same components and the same energy levels, they present different photophysical properties due to the different coordination environment. The band positions are different in the emission spectra. The emission of cycEu-phLa showed a stronger relative intensity of 5D0 7F2 transition whereas the relative intensity of 5D0 7F4 transition was weaker in comparison with cycLa-phEu. We found the cycEu-phLa have higher internal quantum efficiency while the cycEu-phLa have higher sensitizing efficiency, though they have similar external quantum yield. We determined the singlet-triplet intersystem crossing rate with values as ~108 s-1. In Chapter 5, I exploit a dye sensitised upconversion nanoparticle with highly enhanced upconversion emission. I designed and synthesized a new dye by connecting tetraphenylethene (TPE) with the cyanide NIR dye, IR783. The resultant compound (TPEO-IR783) has a quantum yield of 22.46% which is 3 times higher than that of reported UCNP sensitiser (IR806). The TPEO-IR783 exhibits a transparent window in a range of 400 nm to 600 nm, making it suitable sensitiser for upconversion nanoparticles by avoiding reabsorption. The TPEO-IR783 sensitised UCNPs show more than 200-fold upconversion emission than the reported IR806 sensitised UCNPs under the same condition. In Chapter 6, I develop an ytterbium nanoparticle-mediated upconversion system. The system enables the singlet energy transfer from sensitisers to acceptor triplet states without the requirement of intersystem crossing. I evaluate the hybrid upconversion design by IR808 and rubrene acid. While the mixture of IR808 and rubrene acid does not show any upconversion emission, the introduction of an intermediate ytterbium energy level by adding NaGdF4:Yb nanoparticles displays strongly enhanced upconversion emissions. This design bypasses the specific requirement of traditional sensitisers in TTA system, providing a wide range of opportunities in deep tissue applications. Chapter 7 is the experiment sections where details of materials, characterizations, and synthetic procedures in each chapter have been provided.
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Mera-Pirttijarvi, Ross Jalmari. "Targeted multi-modal imaging : using the Ugi reaction with metals." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/targeted-multimodal-imaging-using-the-ugi-reaction-with-metals(00ca616e-b8bd-466a-86dc-d1799851fbd1).html.
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The current 'gold standard method' of detecting cancer relies on microscopic examination by specialised pathologists. However, there are risks associated with surgery and biopsies and so the ability to diagnose cancer and other diseases in a non-invasive manner is highly attractive. There are many imaging techniques suitable for this, each with their own advantages and disadvantages, which can be improved by the use of contrast agents. The incorporation of targeting vectors allows for the specific imaging of desired tissues. Further to this, the incorporation of more than one contrast agent into one imaging agent allows for multi-modal imaging of cancerous tissue and other diseases. This allows for the advantages of different techniques to be used simultaneously and is an emerging field. The methods for the synthesis of these drugs can be synthetically demanding and low yielding due to linear synthetic strategies. The use of multi-component reactions would be a major benefit and the Ugi reaction is particularly attractive due to the incorporation of four components and the biocompatible bis-amide motif of Ugi products. This work serves as an extension to previous work based on Ugi reactions of metal complexes, which showed that amine and carboxylic acid appended lanthanide and carboxylic acid appended d-metal complexes can be used as stable building blocks in the formation of mono-metallic complexes. This work presents the synthesis of aldehyde appended lanthanide complexes and their use in Wittig and Ugi chemistry in the synthesis of mono-metallic complexes. The previously synthesised amine appended lanthanide complexes 1, 3, 4 were also synthesised to be used as a feedstock in subsequent Ugi reactions. A number of carboxylic acid appended d-metal complexes and cyanine dyes were synthesised according literature procedures. Both the bis-acid appended d-metal complexes and cyanine dyes were used unsuccessfully in the Ugi reaction. However, the mono-acid d-metal complexes were used successfully in the Ugi reaction in keeping with previous reports. These were used as the third feedstock for the synthesis of trimetallic complexes along with the aldehyde and amine appended lanthanide complexes via the Ugi reaction. In addition, a number of Ugi reactions were performed on organic compounds. The use of p-toluic acid gave five Ugi compounds, which were characterised and gave the expected results. However, the use of biotin as the carboxylic acid component gave four compounds that were complex to characterise and suggested that the incorporated biotin may not serve as a viable targeting vector. One of the p-toluic acid Ugi products was reacted further and a biotin moiety was incorporated with a (CH2)6 spacer. Spectroscopic evidence suggested that the biotin would still act as a viable targeting vector. Overall, this work serves to set the scene for the synthesis of targeted tri-metallic multi-modal imaging agents using stable metal complexes as building blocks in the Ugi reaction.
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Frietsch, Björn [Verfasser]. "Magnetization Dynamics of Itinerant and Localized Electrons in Lanthanide Metals / Björn Frietsch." Berlin : Freie Universität Berlin, 2015. http://d-nb.info/1080522166/34.
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Shehee, Thomas Charles. "The Americium/lanthanide separation conundrum selective oxidation or soft donor complexants? /." Pullman, Wash. : Washington State University, 2010. http://www.dissertations.wsu.edu/Dissertations/Spring2010/T_Shehee_041510.pdf.
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White, Alex. "Chemical exchange processes in lanthanide (III), dioxouranium (VI) and sodium (I) complexes /." Title page, contents and summary only, 1987. http://web4.library.adelaide.edu.au/theses/09PH/09phw582.pdf.
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Zhang, Lilu. "Synthesis and chemistry of lanthanide complexes with phosphorus ylides, amides or porphyrinate ligands, and of transition metal complexes with polydentate ligands." HKBU Institutional Repository, 1999. http://repository.hkbu.edu.hk/etd_ra/182.
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Clark, Candyce. "Polynuclear biomolecular-supported rare earth coordination compounds : towards a new generation of lanthanide-based drugs." Thesis, Nelson Mandela Metropolitan University, 2014. http://hdl.handle.net/10948/d1020778.
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Galactitol and cis,cis,cis-1,3,5-cyclohexanetriol are polyols that are ideal examples of model compounds for ligands with lanthanide ions as they have their hydroxyl groups in favourable steric arrangement. Several complexes were synthesised with both lanthanide chloride and lanthanide nitrate salts with galactitol, and a variety of structures, both polymeric and monomeric, were observed. In all these complexes, galactitol acted as a bridging molecule between the lanthanide ions. A notable difference was the lanthanum chloride–galactitol complex that showed both chloride and galactitol bridging. The lanthanide nitrate salts formed only polymeric complexes with galactitol. Not all of the complexes showed nitrate ions coordinated to the metal centre, and in the neodymium nitrate– galactitol complex, which shows both monodentate and bidentate coordination of the nitrate groups. The coordination of the nitrate ions was confirmed using both XRD and IR analysis. Two complexes with lanthanide chloride salts and cis,cis,cis-1,3,5-cyclohexanetriol were synthesised and analysed. Lanthanum chloride formed a polymeric complex, which showed extensive chloride bridging between the metal centres. Praseodymium chloride formed a dimeric complex. All complexes were analysed with single-crystal X-ray diffraction, 1H NMR, 13C NMR and IR spectroscopy.
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Seddon, Joanne A. "Aspects of the coordination chemistry of the lanthanide metals with some phosphorous containing ligands." Thesis, Staffordshire University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326441.
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Mkwakwi, Kwakhanya. "Synthesis and characterisation of lanthanide complexes with O,O-donor ligands: towards a new generation of hydrophosphonylation catalysts." Thesis, Nelson Mandela Metropolitan University, 2017. http://hdl.handle.net/10948/11986.
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This study investigates the coordination behaviour of potentially bi- and tridentate O,O- and O,N,O-donor Schiff base ligands with trivalent lanthanide ions. The reactions of lanthanide nitrates with 2-((E)-(tert-butylimino)methyl)-6-methoxyphenol (HL1) have yielded five complexes that are described by the general formula [Ln(HL1)2(NO3)3] (Ln = Ce, Nd, Gd, Ho and Er) and were characterised using physico-chemical techniques including single-crystal X-ray diffraction spectroscopy. The cerium complex crystallised in a triclinic (P-1) space group, while the rest of the complexes crystallised in the monoclinic (P21/c) space group. All the complexes are ten-coordinate adopting a tetradecahedron geometry with two HL1 molecules coordinated through the phenolic and methoxy oxygen atoms. The coordination sphere is completed by six oxygen atoms from three bidentately coordinated nitrate ligands. Electronic data reveals that only the neodymium, holmium and erbium complexes exhibit weak f-f transitions in the visible region. The redox behaviour of the complexes was also investigated and reported. Five novel complexes were prepared by reacting 2-((E)-(tert-butylimino)methyl)phenol (HL2) with [Ln(NO3)3∙xH2O] (Ln = Gd and Dy ; x = 5 or 6) and [LnCl3∙6H2O] (Ln = Nd, Gd and Dy). The crystal structures of the former two complexes are isostructural and the coordination sphere is composed of three HL2 ligands bonded to the metal centre through the phenolic oxygen atom and three nitrate ions coordinated in a bidentate fashion. Both complexes are nine-coordinate and SHAPE analysis reveals that they adopted a muffin geometry. The average Ln-Onitrate and Ln-Ophenolate bond lengths are 2.5078 and 2.2814 Å, respectively. The complexes derived from the chloride salts exhibited an octahedral geometry with four monodentate ligands [Ln-Ophenolate distances range from 2.224(4) to 2.2797(17) Å] coordinating in the equatorial positions and two chloride ions [average Ln-Cl bond length is 2.6527 Å, and average Cl-Ln-Cl angles is 180o] in axial positions. The ligand coordinated through the phenolic oxygen with the phenolic proton migrating to the imino nitrogen to give a zwitterionic form of the ligand. There are weak C-H∙∙∙Cl interactions present and O-H∙∙∙N hydrogen bonds are also observed in the crystal packing. The synthesis of lanthanide complexes with methoxy-6-((E)-(phenylimino)methyl)phenol (HL3) was carried out in methanol to yield two mononuclear complexes with the formulae [Nd(HL3)2(NO3)3] and [Ho(HL3)(NO3)3(DMF)(H2O)]. Single-crystal crystallographic studies shows that the neodymium complex contains two HL3 ligands coordinated bidentately through its methoxide and phenolic oxygen atoms, with three nitrate ions also bonded to the metal in a bidentate manner. The coordination geometry in the holmium complex is composed of only oxygen atoms from the various ligands. Both complexes are ten-coordinate and exhibit a tetradecahedron geometry.
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Luo, Yuxia. "The study of energy transfer and local field effect in lanthanide complexes with high and low symmetry." HKBU Institutional Repository, 2019. https://repository.hkbu.edu.hk/etd_oa/696.
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There are lots of important applications for lanthanides (Ln) because of their unique properties. The properties are closely linked to the environment of the crystal field. Thus, two kind of crystals Cs2NaLn(NO2)6 with high Th point-group symmetry and LnPO4 with monoclinic symmetry were chosen to study quantum cutting and Stokes shift. Quantum cutting is a kind of down-conversion energy transfer in which one excitation ultraviolet photon is transformed into multiple near infrared photons. This phenomenon has been studied in Cs2NaY0.96Yb0.04(NO2)6. The emission from Yb3+ can be excited via the NO2- antenna. The electronic transition of NO2- is situated at more than twice the energy of the Yb3+. At room temperature, one photon absorbed at 470 nm in the triplet state produced no more than one photon emitted. Some degree of quantum cutting was observed at 298 K under 420 nm excitation into the singlet state and at 25 K using excitation into singlet and triplet state. The quantum efficiency was about 10% at 25 K. In Chapter 3, Stokes shift which is the energy shift between the peak maxima in absorption and emission was studied. Stokes shift is related to the flexibility of the lattice and the coordination environment. Cs2NaCe(NO2)6 with 12-coordinated Ce3+ situated at a site of Th symmetry demonstrated the largest Ce-O Stokes shift of 8715 cm−1. The 4f1 ground state and 5d1 potential surfaces have displaced so much along the configuration coordinate that overlap takes place above the 5d1 minimum, leading to thermal quenching of emission at 53 K. A comparison of Stokes shifts with other Ce-O systems with different coordination number demonstrated larger Stokes shifts for Ce3+ ions with higher coordination number. Systematic research about the energy transfer (ET) and energy migration phenomenon is still scarce, although they exist extensively among lanthanide ions. The energy migration in highly doped materials has been stated as very fast or slow, but no experimental proof was reported. In Chapter 4, the ET between Tb3+ and Eu3+ was investigated experimentally and compared with available theoretical models in the regime of high Tb3+ concentrations in 30 nm LaPO4 nanoparticles at room temperature. The ET efficiency approached 100% even for lightly Eu3+-doped materials. The use of pulsed laser excitation and switched-off continuous wave laser diode excitation demonstrated that the energy migration between Tb3+ ions, situated on La3+ sites with a 4 Å separation was not fast. The quenching of Tb3+ emission in singly doped LaPO4 only reduced the luminescence lifetime by about 50% in heavily doped samples. Various theoretical models have been applied to simulate the luminescence decays of Tb3+ and Eu3+-doped LaPO4 samples of various concentrations. The transfer mechanism has been identified as forced electric dipole at each ion. The control of energy transfer rate and efficiency is also an important issue. There are many chemical and geometrical factors that affect energy transfer, including the spectra overlap, the dipole orientation and the distance between the donor and acceptor. The local field of the emission center is another factor that affect the energy transfer by changing the photonic environment. In Chapter 5, the local field effect on the energy transfer between Tb3+ and Eu3+ doped in LaPO4 dispersed in different solvents and solids with a wide range of refractive indexes was studied. The effects of local field (reflected by refractive index) on the ET efficiency and ET rates were clarified that the ET efficiency would decrease with increasing refractive index, while ET rates were independent of the refractive index
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Zha, Shuai. "Lanthanide-based nanomaterials for imaging and inhibition of EBV-related cancers." HKBU Institutional Repository, 2020. https://repository.hkbu.edu.hk/etd_oa/731.
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Nasopharyngeal Carcinoma (NPC) as a typical malignancy that occurs in high-incidence areas, e.g. southern China region, including Hong Kong, and it has aroused wide interests for local researchers to study. The Epstein-Barr virus (EBV) was reported as a vital herpes virus for the growth of NPC. Two significant proteins in EBV, namely Epstein-Barr Nuclear Antigen 1 (EBNA1) and latent infection membrane protein 1 (LMP1) are crucial for virus maintenance and EBV-infected cell development, and essential for cell proliferation and differentiation of EBV latent life cycle, respectively. Thus, inhibition of EBNA1 and LMP1 can be regarded as effective and potent therapy on EBV-associated cancers. In this thesis, the conjugation of core-shell structured upconversion nanoparticles (UCNPs) with distinct EBV-specific peptides including EBNA1 and LMP1 targeting peptides to achieve both impressive inhibition on EBV-positive cancers in vitro/in vivo and visualization on EBV-positive cells with responsive upconversion emission signals were investigated. Taking advantage of lanthanide-based UCNPs, their unique photophysical properties offer deep tissue penetration depth, negligible photobleaching and photocytotoxicity, and therefore provides a solid foundation for convincible theranostic studies. Furthermore, desired inhibitory performance was achieved, it was shown that ~50 mg/mL of nanoprobes can inhibit half of EBV-infected cell viability and only 0.25 mg/tumor of nanoprobes dosage via intravenous injection can prohibit 64.7% of growth inhibition of an EBV-positive tumor
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Leeson, Philip. "Computer modelling of calixerene compounds capable of selectively extracting lanthanide metals from nuclear waste slurries." Thesis, University of Reading, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.484312.
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Scott, Natalie M(Natalie Maree) 1976. "Diverse lanthanoid and lithium complexes with pendant donor amide ligands." Monash University, Dept. of Chemistry, 2001. http://arrow.monash.edu.au/hdl/1959.1/8984.
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Ott, Holger. "Magnetic structures and phase transitions in thin and ultrathin films of heavy lanthanide metals investigated by resonant magnetic X-ray scattering." [S.l. : s.n.], 2004. http://www.diss.fu-berlin.de/2004/186/index.html.
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Wilson, Duane C. "Synthesis, Structure, And Characterization Of Rare Earth(Iii) Transition Metal Cyanides; Lanthanide(Ii) And Metallocene Amidotrihydroborates." Columbus, Ohio : Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1230880974.
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Hanks, John Richard. "Low oxidation state compounds of the group 4 and lanthanide metals with phosphorus containing aromatic ring systems." Thesis, University of Sussex, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367767.
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Payne, Katherine Marie. "Investigations into the Effects of Water Exchange and the Structure of Lanthanide Chelates." PDXScholar, 2016. http://pdxscholar.library.pdx.edu/open_access_etds/3284.
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Lanthanide chelates are effective agents for improving contrast in MR images. Optimizing the relaxation of inner sphere water molecules is a common focus of research in this field. However, the efforts to design an optimal contrast agent have commonly over-looked the relationship of water position and water exchange kinetics. This work explores structural conformation, the impact of very fast water exchange kinetics on hydration, and differing tumbling rates for regioisomers of a number of lanthanide chelates. We have grown crystals of LnDOTMA and obtained structural data by X-ray diffraction that provide a picture of the chelate during water exchange and demonstrate that chelate conformation is associated with water position. We observe increased population of the major isomer with increased water exchange rates in variable temperature 1H NMR studies of HoDOTMA. This suggests that water position and water exchange rates are linked. We therefore recommend that accurate water exchange data be included in the application of the SBM equations when interpreting experimental data. As further support of this recommendation, we measured water exchange kinetics with 17O NMR for the rigid GdNB-DOTMA chelates. These results were used in the fitting of 1H NMRD profiles to establish tumbling parameters. Similar results were also observed in the less rigid GdNB-DOTA, establishing the first identification of regioisomers in these chelates and their biphenyl derivatives. Binding studies of GdBP-DOTA indicate that the side isomer is a more effective agent, but it is the minor species in solution. Our work herein shows that predicting efficacy of contrast agents with SBM equations requires a more complete consideration of chelate hydration (q/r6).
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Ndiaye, Amadou Latyr. "Synthesis and physico-chemical studies on dithiolène complexes of the closed-shell (d10) metals and trivalent lanthanide ions." Besançon, 2009. http://www.theses.fr/2009BESA2007.
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De nos jours, la chimie est utilisée comme outil général pour accéder (synthèse), contrôler (influence des paramètres) et comprendre (étude des propriétés) le matériau. Ceci est rendu possible grâce à deux approches : l'approche «Top- down» et l'approche « Bottom-up ». La première approche est une des bases de la nanotechnologie. La deuxième approche consiste en l'assemblage de systèmes moléculaires possédant des propriétés intrinsèques pour accéder à des matériaux avec de nouvelles propriétés. Ce concept est généralement appelé: «de la molécule au matériau »; et dans ce contexte, la chimie supramoléculaire occupe une position centrale. Le présent travail porte sur la synthèse et l'étude de propriétés des systèmes de métal-dithiolene comportant des ions métalliques et des lanthanides. Le premier chapitre est une introduction générale sur la chimie du dithiolene et des lanthanides. Le deuxième chapitre décrit la synthèse et la caractérisation de systèmes supramoléculaires basées sur des ligands dithiolene neutres. Dans ce chapitre, l'importance des groupes fonctionnels capables de former des interactions non covalentes sera discutée. Le troisième chapitre est consacré à la réactivité de ces ligands dithiolene neutres avec les métaux de transition (d10) tels que CU1, Hg11, et Au1. Ce chapitre décrira la synthèse de complexes supramoléculaires ainsi que leurs propriétés spectroscopiques. Le quatrième chapitre, s'intéresse à la réactivité de ces ligands vis-à-vis des lanthanides trivalents (Nd, Eu, Gd, Tb, Er), la caractérisation des complexes formés ainsi que les propriétés de luminescence en résultant. Notre discussion sera orientée sur le processus de transfert d'énergie («Effet Antenne»), une fois ces ligands coordonnés à un ion lanthanideNowadays, chemistry represents a general tool for accessing (synthesis), controlling (parameters influence) and understanding (study of properties) the material. This is allowed by two possible approaches: the "Top-down" and "Bottom-up". The first approach is a key to nanotechnology. The second approach consists in assembling small systems, with intrinsic properties, to build up macro system with interesting properties. This concept is generally termed as: "from mo/ecu/es to material” and in this context, supramolecular chemistry plays a crucial rote. The present work examines the synthesis and properties of dithiolene systems bearing metal ions and lanthanides. The first chapter is a general introduction on dithiolene chemistry and lanthanides. The second chapter deals with the synthesis and characterisation of supramolecular systems based on neutral dithioiene-like ligands. Ln this chapter importance of non-covalent interactions is discussed. The third chapter concerns the reactivity of these neutral dithiolen like ligands towards d10 transition metals (CU1, Hg11, AU1). This chapter will describe the synthesis of supramolecul complexes and their spectroscopic properties. The fourth chapter deals, with the reactivity of the ligands with lanthanide (Nd, Eu, Gd, Tb, Er) and the characterisation of Ln3+ -dithiolene complexes. The discussion will be oriented on the energy transfer process taking place in these coordination compounds ("Antenna Effect")
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Sturgeon, Matthew Robert. "Cyanide Bridged Multimetallics Derived From Extended Arrays of Alkaline Earth, Rare Earth, and Transition Metals: A Study From Complexes To Catalysts." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1250009077.
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Bunkowske, Beatrice A. "Fluorescence Studies of Metal Organic Frameworks Based on the TATB Ligand, Synthesis and Characterization of an Fe4S4 Analogue and Organic Radicals." Miami University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=miami1323152148.
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Jeffrey, Chris C. "Applications of Single Reference Methods to Multi-Reference Problems." Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc801919/.
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Density functional theory is an efficient and useful method of solving single-reference computational chemistry problems, however it struggles with multi-reference systems. Modifications have been developed in order to improve the capabilities of density functional theory. In this work, density functional theory has been successfully applied to solve multi-reference systems with large amounts of non-dynamical correlation by use of modifications. It has also been successfully applied for geometry optimizations for lanthanide trifluorides.
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Ben, Mefteh Wahid. "Élaboration de films sensibles à base de macromolécules azotées : application aux capteurs chimiques." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10079.
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Ce mémoire est consacré à l'élaboration, au greffage chimique de macrocycles azotés sur des surfaces, le développement des procédés d'élaboration de surfaces sensibles aux ions, l'évaluation de leurs propriétés et la réalisation de prototypes de capteurs chimiques sensibles aux ions. Les macrocycles azotés sont des cyclames sensibles aux ions de métaux de transition et des terpyridines sensibles aux lanthanides. Un capteur sensible à l'ion Fer (III) est réalisé par fonctionnalisation d'un ISFET et de structures de nitrure de silicium/silicium au moyen du greffage de macrocycles azotés de type cyclames sur la surface du dispositif. Un agent de couplage poly(méthylhydrosiloxane) (PMHS) permet cette immobilisation avec une grande efficacité. L'immobilisation d'un dérivé du cyclame (naphtyl-cyclam) sur des surfaces d'or a permis la préparation de capteurs chimiques sensibles aux ions. Les molécules de cyclame ont été déposées sur des électrodes en or par des interactions fortes entre le groupe de naphtyle et la surface d'or. Le film obtenu a été caractérisé en termes de composition, morphologie et propriétés électriques. La conductivité protonique du film naphtyl-cyclam a été mise en évidence par la spectroscopie d'impédance électrochimique (EIS) et la voltampérométrie cyclique (CV). Nous avons montré que l'immobilisation de dérivé de phényl-terpyridine sur des surfaces d'or a permis la préparation des capteurs chimiques sensibles aux ions Gadolinium (III). Les molécules de terpyridine ont été auto-assemblées sur des électrodes en or par des interactions fortes (greffage chimique) avec groupement thiol terminal. Les propriétés électriques de ces interfaces films sensibles/électrolyte sont décrites et des modèles théoriques sont proposés d'après les résultats expérimentaux obtenus par la spectroscopie d'impédance électrochimiqueThis dissertation is devoted to the elaboration, the chemical grafting of aminated macrocycles on surfaces, the development of elaboration processes of surfaces sensitive to the ions, the evaluation of their properties and the fabrication of prototypes of chemical sensors sensitive to the ions. The aminated macrocycles are cyclames, sensitive to transition metal ions and terpyridines sensitive to lanthanides. A chemical sensor sensitive to iron (III) ion is fabricated by means of the functionalization of an ISFET and of silicon nitride/silicon structures through grafting of aminated macrocycles of the cyclam type on to the surface of the device. The coupling agent poly(methylhydrosiloxane) (PMHS) allows such an immobilization with a high efficiency. The immobilization of a derivative of cyclam (naphtyl-cyclam) on gold surfaces allowed the preparation of chemical sensors sensitive to the ions. The molecule of cyclam was deposited on gold electrodes by strong interactions between the naphtyl group and the gold surface. The film obtained was characterized in terms of composition, morphology and electrical properties. The proton conductivity of the N-MNC film was brought out, for the first time, by electrochemical impedance spectroscopy (EIS) and by cyclic voltammetry (CV). We showed that the immobilization of the phenyl-terpyridine derived on gold surfaces allowed the preparation of the chemical sensors sensitive to gadolinium (III) ions. The molecules of terpyridine were self-assembled on gold electrodes by strong interactions (chemical grafting) with a final thiol group. The electrical properties of these sensitive films/electrolyte are described and theoretical models are proposed from the experimental results obtained by the electrochemical impedance spectroscopy
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Neculai, Ana-Mirela. "Synthesis and Reactivity of Rare Earth Metals Complexes with a Nitrogen Donor Ligand. Compounds in Formal Low Oxidation States." Doctoral thesis, [S.l.] : [s.n.], 2003. http://hdl.handle.net/11858/00-1735-0000-000D-F266-8.
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Colman, Tiago André Denck. "Síntese, caracterização e estudo termoanalítico dos nicotinatos de lantanídeos (III) e de ítrio (III), no estado sólido." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/134317.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Foram sintetizados os compostos LnL3•2H2O, sendo que Ln representa os lantanídeos trivalentes (La ao Lu e o ítrio (Y) e o L representa o nicotinato (C6H4NO2--). Os compostos foram sintetizados por adição do ácido nicotínico em carbonatos de lantanídeos e ítrio, sob agitação e aquecimento. A caracterização dos compostos no estado sólido, foi realizada utilizando as técnicas de difratometria de raios X pelo método do pó, complexometria, espectroscopia de absorção na região do infravermelho com transformada de Fourier (FTIR) e pelas técnicas termo analíticas: termogravimetria e calorimetria exploratória diferencial simultâneas (TG-DSC), calorimetria exploratória diferencial (DSC), analise dos gases desprendidos (EGA) por espectroscopia de absorção na região do infravermelho com transformada de Fourier (EGA:TG-FTIR) e termomicroscopia. Os resultados forneceram informações sobre o comportamento térmico, estequiometria dos compostos estudados, cristalinidade, sítios de coordenação e também foi possível identificar os principais produtos gasosos desprendidos durante o aquecimento.
The LnL3•2H2O compounds, where Ln represents the trivalent lanthanides (La to Lu) and yttrium (Y), and L represents nicotinate (C6H4NO2--) were synthesized. The synthesis was perfomed by addition of nicotinic acid lanthanides and yttrium carbonates, with stirring and heating. The characterization of the compounds in the solid state was carried out using the techniques of X-ray diffraction powder pattern, complexometry, infrared spectroscopy (FTIR) and by thermoanalytical techniques: simultaneous thermogravimetry and differential scanning calorimetry (TG-DSC), differential scanning calorimetry (DSC), evolved gas analysises (EGA) by infrared spectroscopy (EGA: TG-FTIR) and thermalmicroscopy.The results provided information on the thermal behavior of the studied as compounds stoichiometry, crystallinity, coordination sites. It was also possible to identify the main gaseous products evolued during heating.
CNPq: 141952/2013-0
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Herron, Fiona Michelle. "A study of digesta passage in rabbits and ringtail possums using markers and models." Thesis, The University of Sydney, 2002. http://hdl.handle.net/2123/483.
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The common ringtail possum (Pseudocheirus peregrinus), a member of the family Pseudocheiridae, is an arboreal folivorous marsupial that feeds predominantly on Eucalyptus foliage. Contrary to the expectation that small body size would inhibit utilisation of a diet containing such high levels of lignified fibre because of relatively low gut volume to body mass ratios and relatively high mass-specific metabolic rates and nutrient requirements (Hume 1999), the ringtail possum is able to survive solely on a diet of Eucalyptus foliage. The rabbit (Oryctolagus cuniculus) is a terrestrial herbivore and is a member of the family Leporidae that feeds predominantly on grasses. The rabbit was proposed as a digesta flow model for the ringtail possum since both are caecotrophic (periodically re-ingest caecal contents) and both are proposed to exhibit a colonic separation mechanism (CSM) where fluids and small, easily digested particles are preferentially returned to the caecum. The rabbit is of value for the modelling process since it is more accessible for experimental manipulation than the ringtail possum. This study investigated a proposal to use digesta passage through the gastrointestinal tract (GIT) of the rabbit as a model of digesta passage for the ringtail possum on the basis that both are caecotrophic caecum fermenters. A number of potential problems were identified with this proposal and investigation of these problems formed the basis for the research described in this thesis. Two main areas were identified as being potentially problematic: 1) fundamental flaws with the particulate markers used in digesta rate of passage studies; and 2) differences in animal behaviour and natural diet between the two subject species which suggested different digestive strategies and hence different patterns of digesta flow through the GIT. The proposed digesta passage markers were lanthanide metals (Dy, Tm, Eu and Yb) attached to either fibrous particles (1200 - 600�m) or formalin-fixed rumen bacteria (20 � 0.2�m). These markers were shown to not be of the assumed size classes and the extent of lanthanide metal binding differed between the four metals used. An effect due to method of dosing was also observed. The findings of marker inconsistencies caused major limitation to model development and further research is necessary to clarify these markers. The proposal to use digesta flow in the rabbit GIT as a model for digesta flow in the ringtail possum was shown to be idealistic due to the differences in anatomy and behaviour observed between the two herbivores. Laboratory observations, time series analysis and compartmental modelling confirmed the differences between the animals. This study showed: 1) the GIT of the rabbit was more complex both anatomically and functionally than that of the ringtail possum; 2) behaviour affecting digesta passage of the rabbit and ringtail were different and; 3) compartmental models confirmed the anatomical and behavioural findings. Digesta passage in the rabbit could not be modelled mathematically using data on digesta passage due to complexities of the system. In contrast, a basic model was constructed for digesta passage in the ringtail possum. On the basis of these findings, the research hypothesis "that digesta passage in rabbits is similar to that in ringtail possums" was rejected.
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Herron, Fiona Michelle. "A study of digesta passage in rabbits and ringtail possums using markers and models." University of Sydney. Biology, 2002. http://hdl.handle.net/2123/483.
Full textAbstract:
The common ringtail possum (Pseudocheirus peregrinus), a member of the family Pseudocheiridae, is an arboreal folivorous marsupial that feeds predominantly on Eucalyptus foliage. Contrary to the expectation that small body size would inhibit utilisation of a diet containing such high levels of lignified fibre because of relatively low gut volume to body mass ratios and relatively high mass-specific metabolic rates and nutrient requirements (Hume 1999), the ringtail possum is able to survive solely on a diet of Eucalyptus foliage. The rabbit (Oryctolagus cuniculus) is a terrestrial herbivore and is a member of the family Leporidae that feeds predominantly on grasses. The rabbit was proposed as a digesta flow model for the ringtail possum since both are caecotrophic (periodically re-ingest caecal contents) and both are proposed to exhibit a colonic separation mechanism (CSM) where fluids and small, easily digested particles are preferentially returned to the caecum. The rabbit is of value for the modelling process since it is more accessible for experimental manipulation than the ringtail possum. This study investigated a proposal to use digesta passage through the gastrointestinal tract (GIT) of the rabbit as a model of digesta passage for the ringtail possum on the basis that both are caecotrophic caecum fermenters. A number of potential problems were identified with this proposal and investigation of these problems formed the basis for the research described in this thesis. Two main areas were identified as being potentially problematic: 1) fundamental flaws with the particulate markers used in digesta rate of passage studies; and 2) differences in animal behaviour and natural diet between the two subject species which suggested different digestive strategies and hence different patterns of digesta flow through the GIT. The proposed digesta passage markers were lanthanide metals (Dy, Tm, Eu and Yb) attached to either fibrous particles (1200 - 600�m) or formalin-fixed rumen bacteria (20 � 0.2�m). These markers were shown to not be of the assumed size classes and the extent of lanthanide metal binding differed between the four metals used. An effect due to method of dosing was also observed. The findings of marker inconsistencies caused major limitation to model development and further research is necessary to clarify these markers. The proposal to use digesta flow in the rabbit GIT as a model for digesta flow in the ringtail possum was shown to be idealistic due to the differences in anatomy and behaviour observed between the two herbivores. Laboratory observations, time series analysis and compartmental modelling confirmed the differences between the animals. This study showed: 1) the GIT of the rabbit was more complex both anatomically and functionally than that of the ringtail possum; 2) behaviour affecting digesta passage of the rabbit and ringtail were different and; 3) compartmental models confirmed the anatomical and behavioural findings. Digesta passage in the rabbit could not be modelled mathematically using data on digesta passage due to complexities of the system. In contrast, a basic model was constructed for digesta passage in the ringtail possum. On the basis of these findings, the research hypothesis "that digesta passage in rabbits is similar to that in ringtail possums" was rejected.
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Heller, Anne. "Spektroskopische Untersuchungen zur Komplexbildung von Cm(III) und Eu(III) mit organischen Modellliganden sowie ihrer chemischen Bindungsform in menschlichem Urin (in vitro)." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-70475.
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Dreiwertige Actinide (An(III)) und Lanthanide (Ln(III)) stellen im Falle ihrer Inkorporation eine ernste Gefahr für die Gesundheit des Menschen dar. An(III) sind künstlich erzeugte, stark radioaktive Elemente, die insbesondere bei der nuklearen Energiegewinnung in Kernkraftwerken entstehen. Durch Störfälle oder nicht fachgerechte Lagerung radioaktiven Abfalls können sie in die Umwelt und die Nahrungskette des Menschen gelangen. Ln(III) sind hingegen nicht radioaktive Elemente, die natürlicherweise vorkommen und für vielfältige Anwendungen in Technik und Medizin abgebaut werden. Folglich kann der Mensch sowohl mit An(III) als auch Ln(III) in Kontakt kommen bzw. sie inkorporieren. Es ist daher von enormer Wichtigkeit, das Verhalten dieser Elemente im menschlichen Körper aufzuklären. Während makroskopische Vorgänge wie Verteilung, Anreicherung und Ausscheidung bereits sehr gut untersucht sind, ist das Wissen hinsichtlich der chemischen Bindungsform (Speziation) von An(III) und Ln(III) in Körperflüssigkeiten noch sehr lückenhaft. In der vorliegenden Arbeit wurde daher erstmals die chemische Bindungsform von Cm(III) und Eu(III) in natürlichem menschlichem Urin (in vitro) spektroskopisch aufgeklärt und die gebildeten Komplexe identifiziert. Hierzu wurden auch grundlegende Untersuchungen zur Komplexierung von Cm(III) und Eu(III) in synthetischem Modellurin sowie mit den urinrelevanten organischen Modellliganden Harnstoff, Alanin, Phenylalanin, Threonin und Citrat durchgeführt und die noch unbekannten Komplexbildungskonstanten bestimmt. Abschließend wurden alle experimentellen Ergebnisse mit Literaturdaten und Vorherberechnungen mittels thermodynamischer Modellierung verglichen. Auf Grund der hervorragenden Lumineszenzeigenschaften von Cm(III) und Eu(III) konnte insbesondere auch die Eignung der zeitaufgelösten laserinduzierten Fluoreszenzspektroskopie (TRLFS) als Methode zur Untersuchung dieser Metallionen in unbehandelten, komplexen biologischen Flüssigkeiten demonstriert werden. Die Ergebnisse dieser Arbeit liefern damit neue Erkenntnisse zu den biochemischen Reaktionen von An(III) und Ln(III) in Körperflüssigkeiten auf molekularer Ebene und tragen zu einem besseren Verständnis der bekannten, makroskopischen Effekte dieser Elemente bei. Darüber hinaus sind sie die Grundlage weiterführender in-vivo-UntersuchungenIn case of incorporation, trivalent actinides (An(III)) and lanthanides (Ln(III)) pose a serious health risk to humans. An(III) are artificial, highly radioactive elements which are mainly produced during the nuclear fuel cycle in nuclear power plants. Via hazardous accidents or nonprofessional storage of radioactive waste, they can be released in the environment and enter the human food chain. In contrast, Ln(III) are nonradioactive, naturally occurring elements with multiple applications in technique and medicine. Consequently it is possible that humans get in contact and incorporate both, An(III) and Ln(III). Therefore, it is of particular importance to elucidate the behaviour of these elements in the human body. While macroscopic processes such as distribution, accumulation and excretion are studied quite well, knowledge about the chemical binding form (speciation) of An(III) and Ln(III) in various body fluids is still sparse. In the present work, for the first time, the speciation of Cm(III) and Eu(III) in natural human urine (in vitro) has been investigated spectroscopically and the formed complex identified. For this purpose, also basic investigations on the complex formation of Cm(III) and Eu(III) in synthetic model urine as well as with the urinary relevant, organic model ligands urea, alanine, phenylalanine, threonine and citrate have been performed and the previously unknown complex stability constants determined. Finally, all experimental results were compared to literature data and predictions calculated by thermodynamic modelling. Since both, Cm(III) and Eu(III), exhibit unique luminescence properties, particularly the suitability of time-resolved laser-induced fluorescence spectroscopy (TRLFS) could be demonstrated as a method to investigate these metal ions in untreated, complex biofluids. The results of this work provide new scientific findings on the biochemical reactions of An(III) and Ln(III) in human body fluids on a molecular scale and contribute to a better understanding of the known macroscopic effects of these elements. Furthermore, they are the basis of subsequent in vivo investigations
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Gathergood, Nicholas Keith Peter. "Chiral cyclopentadienyl lanthanide and transition metal complexes." Thesis, University of Southampton, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284648.
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Congreve, Aileen. "Responsive lanthanide complexes for metal ion sensing." Thesis, Durham University, 2004. http://etheses.dur.ac.uk/3668/.
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The speciation and distribution of zinc (II) within cells is not well established and the range of zinc (II) probes available are of limited use. The quest was to develop responsive lanthanide complexes to bind selectively and respond (by change in hydration state) to biologically relevant concentrations of zinc at physiological pH for possible application in MRI and luminescence. A pyridyl sulfonamide ligand with an a-CH(_2)NHSO(_2)CF(_3) substituent was found to have the desired properties for strong zinc (II) coordination. The presence of a methyl group at 6', inhibited the formation of related square planar copper (II) complexes. Pyridyl amide appended europium and gadolinium (III) complexes, based on cyclen were developed with C(_2) and (C_3) spacers separating the macrocyclic ring and the amide. The mono-aqua C(_2) complex exhibited fast water exchange, due to the steric hindrance of the seven-membered chelate between the amide carbonyl and the lanthanide centre. The increase in steric hindrance caused by the eight-ring chelate in the C(_3) analogue rendered it q = 0. A trifluoromethanesulfonamide moiety at the 6' position of the pyridine group resulted in a mono-aqua complex for the C(_2) and C(_3) appended systems. This system showed no change in hydration state on addition of Zn(^2+). The addition of a-N- carboxyalkyl groups to give a GdaD03A system resulted in the formation of q = 2 complexes which showed no zinc (II) responsive properties. However, the C(_2)- linked species exhibited a high binding affinity to HSA which resulted m a dramatic increase in the relaxivity. Eu and Gd complexes of an octadentate N(_5)O(_3) pyridyl sulfonamide containing ligand were developed as pH and pZn responsive probes. The pyridyl nitrogen bound irreversibly to the lanthanide centre, resisting protonation even in the presence of zinc and copper ions, for which the pyridyl sulfonamide group has an establiblished high affinity.
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Phelan, Gregory David. "The synthesis, design, and applications of lanthanide cored complexes /." Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/8572.
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Minhas, Ravinder Iaur. "Chemistry of low-valent early transition metals and lanthanides." Thesis, University of Ottawa (Canada), 1996. http://hdl.handle.net/10393/9526.
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Reactions of trans-TiCl$\rm\sb2(TMEDA)\sb2$ with two equivalents of RONa gave the paramagnetic linear trimeric (Ti$\rm\sb3(PhO)\sb9(TMEDA)\sb2\rbrack$ (2.1), dimeric (Ti(OR)Cl(TMEDA)) $\sb2(\mu$-OR)$\sb2$ (2.2) (R = 3,5-(t-Bu)$\rm\sb2C\sb6H\sb3\rbrack$ or monomeric (Ti(OR)$\rm\sb4\rbrack\lbrack Li(TMEDA)\sb2\rbrack$ (2.7) (R = 2,6-(iPr)$\rm\sb2C\sb6H\sb3$), indicating that the role of steric hindrance not only controls the geometry and the nuclearity of the complex, but also stabilizes the +3 oxidation state. Conversely, in the case of vanadium, it was possible to isolate and characterize monomeric and neutral V(II) aryloxides with a variety of coordination geometries like square-planar and saddle-shaped. Less bulky phenols give monomeric or dimeric products after disproportionation and oxidation. Similar to the case of titanium, vanadium aryloxides do not show any interaction with dinitrogen. Reaction of V ((2-OMe)C$\rm\sb6H\sb4O\rbrack\sb2$(TMEDA) (4.7) with Me$\rm\sb3SiCHN\sb2$ gave $\{$ ((2-OMe)C$\rm\sb6H\sb4O\rbrack\sb2V\}\sb2 \lbrack\mu$-NNCHSiMe$\sb3\rbrack\sb2$ co-crystallized with $\{$ ((2-OMe)C$\rm\sb6H\sb4O\rbrack\sb2V\}\sb2 \lbrack\mu$-(2-OMe)$\rm C\sb6H\sb4O\rbrack\sb2$ (4.14). The structures of these complexes were determined by X-ray analysis. The synthesis and reactions of ionic Ti(III) amides with RLi are discussed. Sterically demanding alkyl groups (R = CM$\rm\sb2CMe\sb3,\ CH\sb2SiMe\sb3,\ CH\sb2CMe\sb2Ph\rbrack$ led to disproportionation and isolation of Ti(IV) complexes of the formulation ((Cy$\rm\sb2N)\sb2TiR\sb2\rbrack$ whereas with MeLi & BzLi, (Cy$\rm\sb2N)\sb2TiR\sb2$Li(TMEDA) (R = Bz (3.4a), Me (3.4b)) was formed, thus retaining the +3 oxidation state of titanium. Thermolysis of (Cy$\rm\sb2N)\sb2TiNf\sb2$ gave (Cy$\rm\sb2N)\sb2TiCH\sb2C(Me)\sb2C\sb6H\sb4$ (3.10) after losing a molecule of neophane. The ability of three-center chelating ligands (such as formamidinates or benzamidinates) to form dinuclear complexes with a short M-M contact was studied in order to understand the role of bridging ligands in promoting or disfavoring the dinuclear aggregation and to determine the extent of intermetallic separation in such species. The reaction of Li amidinates with trans-VCl$\rm\sb2(TMEDA)\sb2$ gave dinuclear ((CyNC(H)NCy)$\rm\sb2V\rbrack\sb2$ (5.3), monomeric (CyNC(Me)NCy) $\rm\sb2V(THF)\sb2$ (5.7) and (Me$\rm\sb3SiNC(Ph)NSiMe\sb3\rbrack\sb2V(THF)\sb2$ resulted in the formation of V(III) complex (CyNC(Me)NCy) $\sb3$V (5.6) whereas in the case of (Me$\sb3$SiNC(Ph)NSiMe$\sb3\rbrack\sb2$V(THF)$\sb2$ a novel dinitrogen complex ($\{\rm Me\sb3SiNC(Ph)NSiMe\sb3\}\sb2V\rbrack\sb2(N\sb2)$ (5.12) was formed. All these complexes could also be synthesized via reduction of V(III) amidinates. Reactions of LiNR$\sb2$ with SmCl$\sb3$(THF)$\sb3$ in a 2:1 molar ratio gave Sm(III) amides with different formulations and structures depending upon the R group of the amide. Dimeric ((Cy$\rm\sb2N)\sb2Sm(THF)(\mu$-Cl)) $\sb2$ (6.1) was obtained from the reaction of SmCl$\sb3$(THF)$\sb3$ with Cy$\sb2$NLi whereas ((i-Pr$\sb2\rm N)\sb2SmCl\sb3(LiTMEDA)\sb2$) (6.2) was obtained from the amide, iPr$\sb2$NLi under similar reaction conditions but in the presence of TMEDA. The reactivity of these amides was studied which gave another variety of Sm(II) amides like ((Cy$\rm\sb2N)\sb6Sm\sb4Cl\sb6(THF)\sb2$) (6.3) and ((Cy$\rm\sb2N)\sb4$SmLi(THF)) (6.4). Attempts to reduce (6.1) gave either metallic samarium or Sm(Cy$\rm\sb2N)\sb3$(THF) (6.5). The direct synthesis of a Sm(II) amide was possible only with Ph$\sb2$N, the salt having no $\alpha$-hydrogen. Using Ph$\sb2$N as the ligand, both ionic (Sm(Ph$\rm\sb2N)\sb4Na\sb2(TMEDA)\sb2$) (6.6) and neutral (Sm(Ph$\rm\sb2N)\sb2(THF)\sb4\rbrack$ (6.7) complexes were obtained. The structures of all these complexes are demonstrated by X-ray analysis.
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Casely, Ian J. "Electropositive metal N-heterocyclic carbene complexes." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/3873.
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The first chapter is an introduction to the f-elements, with a focus on the synthesis and chemistry of tetravalent cerium complexes. The synthesis, characterisation and reactivity of carbenes, particularly N-heterocyclic carbenes (NHCs), and anionic-functionalised NHC ligands is discussed. The synthesis and reactivity of s-block, Group three and fblock NHC complexes is reviewed. The synthesis of the alcohol-functionalised unsaturated imidazolium proligand, [H2L]I [H2L = HOCMe2CH2(1-CH{NCHCHNiPr})], is extended to saturated imidazolinium analogues, [H2LR]X, [HOCMe2CH2(1-CH{NCH2CH2NR})]X (R = iPr, abbreviated to P; R = Mes, abbreviated to M; R = Dipp, abbreviated to D, X = Cl, I). Mono-deprotonation results in the isolation of bicyclic imidazolidines HLR, which can be ring-opened and silylated by treatment with Me3SiI, to afford [HLR, OSiMe3]I, R = iPr and Mes. Further deprotonation of HLR with MN"2 (M = Mg, Zn; N" = N(SiMe3)2) affords LRMN" (M = Mg and Zn) and ZnLR 2. These complexes proved active for the polymerisation of raclactide at room temperature without the need for an initiator. The third chapter focuses on cerium chemistry. Repetition of the literature synthesis of CeIV tert-butoxide compounds affords the unsolvated Ce(OtBu)4 and also the cluster Ce3(OtBu)11. Treatment of Ce(OtBu)4 with HL did not yield a CeIV-NHC complex, but one bearing a tethered imidazolium group, (OtBu)3Ce( -OtBu)2( -HL)Ce(OtBu)3. The synthesis of a CeIII-NHC complex, CeL3, and the oxidation of this forms an unprecedented CeIV-NHC complex, CeL4, via ligand redistribution; the complex contains two bidentate ligands and two alkoxide-tethered free NHC groups. Functionalisation of the free NHCs with boranes affords the adducts Ce(L)2(L-B)2, where B = BH3 or 9-BBN (9-Borabicyclo[3.3.1]nonane). A number of cerium complexes of the saturated-backbone NHC, LR, LRCeN"2 and LR 2CeN", have been synthesised and their oxidation chemistry and reactivity investigated. The final chapter contains an NMR study of the synthesis of a series of yttrium LR adducts, LP xYN"(3-x) (x = 1, 2 or 3), and of the synthesis of uranium complexes LRUN"2, R = Mes or Dipp, including a range of small molecule reaction chemistry. The uranyl NHC complexes, UO2LR 2, R = Mes or Dipp, have also been synthesised and characterised; these possess very high frequency carbene carbon chemical shifts.
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Annand, Judith. "Soluble molecular siloxane complexes of the lanthanides." Thesis, University of Liverpool, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367203.
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Sulway, Scott Andrew. "Polar organometallic precursors to amido-bridged transition metal and lanthanide cage compounds." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/polar-organometallic-precursors-to-amidobridged-transition-metal-and-lanthanide-cage-compounds(34f62a8d-e349-4e4d-947d-d01503cbcfba).html.
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This project involved utilising the Brønsted basic nature of polar organometallic compounds DyCp3 and [Fe{N(SiMe3)2}2], to deprotonate organic compounds that contain an acidic H-N bond to form low co-ordinate compounds that can then aggregate together to form polynuclear cage compounds. Using DyCp3 in a reaction with BtaH, a dimer formed, [(η5-Cp)2Dy(µ-Bta)]2. This dimer is a single-molecule magnet. [(η5-Cp)2Dy(µ-Bta)]2 was compared to a previously reported compound [(η5-Cp)2Dy{µ-N(H)pmMe2}]2 which, despite having a similar structure to [(η5-Cp)2Dy(µ-Bta)]2, is not a SMM. Synthesis of a chlorine- bridged dimer [(η5-Cp)2DyCl(THF)]2 and subsequent magnetic measurements confirmed that [(η5-Cp)2DyCl(THF)]2 is a SMM. Removal of the THF ligand from [(η5-Cp)2DyCl(THF)]2 was achieved via sublimation. The product of this sublimation was a mixture of two different polymorphs of the same compound, [(η5-Cp)2DyCl]2 and [(η5-Cp)2DyCl]∞. [(η5-Cp)2DyCl]2 was shown to be a SMM, and [(η5-Cp)2DyCl]∞ was shown to display SMM behaviour. [(η5-Cp)2DyCl]∞ had the largest energy barrier to relaxation of magnetisation for any known homospin dysprosium(III) compound. Using [Fe{N(SiMe3)2}2] in a reaction with HppH resulted in the formation of [{Fe{N(SiMe3)2}(hpp)2}2Fe]. [{Fe{N(SiMe3)2}(hpp)2}2Fe] displayed anti-ferromagnetic exchange between the iron(II) centres which resulted in a ground spin state of S = 2. Reacting [Fe{N(SiMe3)2}2] with BtaH resulted in the formation of [{(Me3Si)2NFe}4Fe(Bta)6]. Despite repeated attempts [{(Me3Si)2NFe}4Fe(Bta)6] could not be re-synthesised. An alternative “one pot” synthetic method was attempted, this resulted in the formation of [Fe{N(SiMe3)2}2(LiBta)]2. The structure of [Fe{N(SiMe3)2}2(LiBta)]2 was described using ring-ladder principles and magnetic studies revealed weakly anti-ferromagnetically coupled iron(II) centres which displayed a large zero-field splitting. Extension of the one-pot synthetic route to the use of tin halides was conducted. Using SnCl2 in the one-pot synthetic route resulted in the formation of [{(Me3Si)2N}8Sn8Li8Cl4(Bta)12]. Whilst using SnBr2 resulted in the formation of the compound [{(Me3Si)2N}8Sn8Li8Br4(Bta)12]. The charge separated compound [{(THF)2Li(Bta)}3{Li(THF)}]2[SnI4] was the result of using SnI2 in the one-pot method.
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Fucassi, Flavia. "Design and synthesis of novel ligands for lanthanide complexation." Thesis, University of Brighton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311438.
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Cepeda, Céline. "Synthèse et caractérisation de sondes luminescentes peptidiques pour l'imagerie de cations." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAV072/document.
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Les ions métalliques sont essentiels pour le vivant. Une machinerie complexe tant au niveau cellulaire qu’au niveau de l’organisme entier permet de réguler finement leurs concentrations. Un dérèglement de leur homéostasie est souvent associé à des maladies. Afin de mieux comprendre les processus biologiques dans lesquels ces métaux sont impliqués, il est important de pouvoir les détecter, les suivre et les quantifier. Le but de ma thèse a été de synthétiser des sondes luminescentes pour la détection sélective du Zn2+ et du Cu+ au sein de cellules. Nous avons préparé et caractérisé des macromolécules sophistiquées présentant les qualités requises pour un tel objectif. Ces molécules sont synthétisées par méthode convergente mettant en jeu différentes ligations chimio sélectives.Nous avons développé une famille de sondes sélectives de Zn2+, intensiométriques ou ratiométriques et émettant dans le visible ou dans le proche infrarouge. En vue de réaliser des sondes pour l’imagerie cellulaire par microscopie confocale, nous avons mis au point une méthode de synthèse pour ajouter différentes séquence de pénétration à ces sondes. Elles ont été ensuite testées in cellulo. Bien qu’elles ne permettent pas la détection du zinc, elles ont néanmoins permis d’identifier une séquence de pénétration permettant une internalisation cellulaire. Nous avons ensuite développé une sonde incorporant deux complexes de lanthanides (terbium et europium) pour la détection du Cu+. Cette sonde répond parfaitement à la présence de Cu+ avec un signal ratiométrique. Son comportement contre intuitif a été étudié grâce à la synthèse et la caractérisation de différents « mutants »Metal ions are essential for life. Complex machineries at both the cellular and the whole organism levels regulate finely their concentrations. A disruption of their homeostasis can lead to disorders and serious diseases. In order to better understand the biological processes involving these metals, it is important to be able to detect, track and quantify them. The aim of my PhD was to develop luminescent probes for the detection of Zn2+ and Cu+. We prepared and characterized sophisticated molecules exhibiting the qualities required for this goal. These molecules were synthesized by convergent methods involving various chemoselective ligations. We developed a family of selective zinc probes, inensiometric or ratiometric, which emitted in the visible or near infra red. In order to elaborate probes for cellular imaging by confocal microscopy, we designed a synthetic pathway to add different penetrating peptides to these probes. They were tested in cellulo. Although they didn’t demonstrate zinc detection, they allowed identification of the penetrating sequence which permitted the cellular internalisation. We then developed a probe which incorporated two lanthanide complexes (terbium and europium) for the Cu+ detection. This probe responds perfectly to the presence of Cu+ with a ratiometric signal. Its counter-intuitive behaviour was studied thanks to the synthesis and the characterisations of different « mutants »