Dissertations / Theses on the topic 'Lanthanide Chemistry'
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1
Liu, Sung Ying. "Steric effects in Lanthanide pyrazolylborate chemistry." Thesis, University College London (University of London), 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.561271.
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Creaser, Dale Abel. "Aspects of composite lanthanide oxide chemistry." Thesis, University of Nottingham, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334547.
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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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Xu, Xiaohan. "Acidity of Lanthanide Clusters." University of Akron / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron1619532111562154.
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Farkas, Ildiko. "Coordination Chemistry of Actinide and Lanthanide Ions." Doctoral thesis, KTH, Chemistry, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3236.
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Farkas, Ildikó. "Coordination chemistry of actinide and lanthanide ions /." Stockholm, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3236.
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Affholter, Kathleen. "Synthesis and crystal chemistry of lanthanide allanites." Diss., Virginia Tech, 1987. http://hdl.handle.net/10919/37332.
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Metamictization and complex chemistry are major obstacles to the crystal chemical characterization of natural allanites. To overcome these problems, allanites, Ca(REE)Fe²+Al₂Si₃O₁₂(OH), where REE = La, La-Ce, Ce, Nd, Sm, Eu, Gd, Er, Dy, Yb and Y have been synthesized hydrothermally from unbuffered and buffered oxide mixes at 500 to 650°C, 5.5 kbar (550 MPa), and 700 to 725°C, 4 kbar (400 MPa). Although allanite is readily synthesized, high yields are obtained only for allanite-(LREE) compositions, and end"member composition is obtained only for allanite-(La). Er and Yb ions are too small to substitute at the A(2) site in allanite, but a small amount can substitute at the VI~coordinated M(3) site. Fe²+ in the M(3) site favors LREE substitution, which supports the contention that allanite is Ce'selective.Ph. D.
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Timmins, Phillipa L. "Dinuclear luminescent lanthanide complexes." Thesis, University of York, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274520.
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Lilley, Johnathon Robert. "Lanthanide nanoparticles in immunodiagnostics." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8157/.
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This thesis shows the surface functionalisation of gold nanoparticles with surface active, luminescent Eu complexes and free light chain antibodies, to produce free light chain antibody functionalised gold nanoparticles which show characteristic, Eu luminescence. We show how these particles can be used in the development of a novel FRET based assay whereby the Eu luminescence is quenched on addition of free light chain specific antibody, labelled with a suitable organic FRET acceptor for Eu luminescence as measured by lifetime measurements. We show how these particles can be used to develop a competitive immunoassay to measure the concentration of free light chain antibodies. We also report the preparation of a novel functionalised dibenzoylmethane molecule with a thiol surface active group as to functionalise gold nanoparticles which can bind and sensitize Eu ions.
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Sudhakaran, Pillai S. "Luminescent materials based on Lanthanide ions." Thesis, Kingston University, 2010. http://eprints.kingston.ac.uk/20413/.
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The inclusion of lanthanide (III) (Ln[sup]3+) ions into polymers by “covalent” bonding has applications. Heteroleptic hydrotris(pyrazolyl)borate crotonate and cinnamate complexes were synthesised for reasons that, firstly, knowledge of the polymerisable double bond was helpful in establishing the conditions of any copolymerisation reaction; secondly, the chosen ligands are very good at receiving energy in the UV region; and thirdly, lanthanide complexes might undergo changes in properties, on moving between adjacent lanthanide ions, allowing potentially convenient isolations of pure materials at the monomer production stage, or even at the polymerisation stage. For both complexes, two classes of target complex were identified: the mononuclear (Er-Lu) and dinuclear (La-Ho). Mononuclear forms were identified by MS, [sup]1H NMR and elemental analysis and dinuclear forms were characterised by X-ray crystallography. For heteroleptic hydrotris(pyrazolyl)borate crotonate and cinnamate complexes, the ligands act as antennae for receiving and then transferring energy to metal ions and these complexes were studied in several homogeneous and heterogeneous copolymers as well as in rigid PMMA or polystyrene matrices. Luminescence decay of these complexes depends on the distance between the metal and C-H oscillators so the cinnamate complexes showed better luminescence life-times compared to crotonate complexes. The copolymer system helped to reduce the concentration quenching compared to corresponding metal complex / polymer blend systems. The thermal stabilities of the complex monomers were increased by incorporating them into polymer chains. Europium crotonate and cinnamate complexes in the poly(p-phenylenevinylene) (PPV) precursor blends showed the characteristic emission of europium, and the emission from PPV was quenched by increasing the europium content in the PPV precursor blends.
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Bheemala, Veera Manesh. "Sol-Gel Synthesis of Lanthanide-Doped Aluminosilicate Glasses." Thesis, Southern Illinois University at Edwardsville, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1601351.
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Doping Praseodymium into Al-Si glass has potential applications in permanent holographic data storage and other optical devices. For this we are using the sol-gel method to produce glass monoliths at relatively low temperatures. The silicon precursor is tetraethylorthosilicate (TEOS) and aluminum tri-sec butoxide (ATSB) is the aluminum precursor. TEOS is hydrolyzed in ethanol with HCl as a catalyst. ATSB is then added, as well as praseodymium chloride in water. To prevent cracking we use dimethyl formamide (DMF) as a drying control chemical additive (DCCA). The solution is poured into a polymethylpentene cylinder and maintained at 40°C and the temperature is raised to 150°C to dry and shrink the sample. Samples prepared by this method are amorphous, as indicated by X-ray diffraction. The final aim of this research is to produce optically clear, fracture less monoliths by varying aging, shape and drying conditions.
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Motson, Graham Robert. "Coordination chemistry of 3-(2'-pyridyl) pyrazole derivative ligands." Thesis, University of Bristol, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391153.
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Bruce, James I. "Supramolecular photochemistry of lanthanide complexes." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308689.
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Amoli, Hossein Salar. "Chromatographic investigation of some lanthanide complexes." Thesis, University of Salford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.258243.
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Lau, Kwok-kin. "The chemistry of lanthanide complexes with amide and carboxylate ligands /." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36584654.
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林偉興 and Wai-hing Lam. "The chemistry of lanthanide complexes containing aminophenol and carboxylate ligands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31241906.
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Lau, Kwok-kin, and 劉國健. "The chemistry of lanthanide complexes with amide and carboxylate ligands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B45015491.
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Lam, Wai-hing. "The chemistry of lanthanide complexes containing aminophenol and carboxylate ligands /." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23316615.
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Takasaki, Bryan K. "Lanthanide ions in the development of artificial nucleases." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28535.
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The kinetics and mechanism of hydrolysis of both activated and unactivated phosphate diesters in the presence of aqueous solutions of Ce(III) salts are studied in detail. In the presence of 20 mM Ce$ rm (ClO sb4) sb3 (pH 8, 37 sp circ C)$ a DNA dinucleotide (dApdA) is converted to the nucleoside (dA) and inorganic phosphate with a half-life of approximately 100 minutes. This reaction is oxygen dependent and a mechanism involving the activation of oxygen by Ce(III) to give a Ce(IV) coordinated peroxide dianion as the active species is proposed.The addition of 20 mM hydrogen peroxide to 2mM La(III) (pH 7.0, 25$ sp circ$C) results in a 34,000 fold increase in the rate of BNPP hydrolysis over that observed in the presence of 2mM La(III) alone and an overall 5 x l0$ sp8$ fold rate increase over the uncatalyzed rate. Incorporation of $ sp{18}$O from hydrogen peroxide into the inorganic phosphate product and evidence from the reaction kinetics and potentiometric titrations indicate that the mechanism involves nucleophilic attack of a La(III) coordinated peroxide dianion upon the substrate.
La(III) hydroxide clusters formed from the combination of La(III) (20 mM) and NaOM (40 mM) rapidly converts an RNA dinucleotide (ApA) to the monophosphates (2$ sp prime$-AMP and 3$ sp prime$-AMP) (t$ sb{1/2}$ = 8 sec at pH 8.7, 20$ sp circ$C). The presence of molecular oxygen does not improve the efficiency of Ce(III) in cleaving ApA; however, it does assist in the cleavage of the monophosphates which are not cleaved by Ce(III) in the absence of O$ sb2$ or La(III).
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Cullen, Thomas Donovan. "Hydroxyl radical reaction and lanthanide ion complexation kinetics of DTPA." Thesis, California State University, Long Beach, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=1524188.
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Williams, Mark. "Lanthanide alkoxide complexes for use in asymmetric synthesis." Thesis, University of Liverpool, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264785.
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Lim, Soyoung. "Part I. Syntheses and characterization of hydrogen-bridged Lanthanide(II)-Boron complexes ; Part II. Syntheses and characterization of Cyanide-bridged Lanthanide (III)-Palladium complexes /." The Ohio State University, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486399451960783.
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Zhang, Zhonghao. "Lanthanide-Containing Functional Materials - From Molecular Level to Bulk Level." Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/613124.
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This work is a comprehensive summary of research projects the author conducted when attending the PhD program at the University of Arizona. Research topics cover the structural chemistry of lanthanide-amino-acid clusters, optical up-conversion properties of lanthanide based nanomaterials, magnetic and luminescent properties of lanthanide metal-organic frameworks (MOFs), as well as two research projects focusing on transition metal MOFs, which were derived from lanthanide metal-organic framework projects. In chapter 2, the discovery of halide anion templated lanthanide-histidine hydroxide cluster and a comprehensive study of the influence of anionic size on cluster nuclearity are discussed. Both Cl⁻ and Br⁻ were able to serve as template anions assisting the formation of pentadeca-nuclear lanthanide hydroxide clusters for Nd, Gd and Er. When I⁻ was used as the template anion, pentadeca-nuclear hydroxide cluster only formed in neodymium case. In erbium case a dodeca-nuclear hydroxide cluster formed when I⁻ was used as template ion. However I⁻ was not effective in assisting the formation of high nuclearity gadolinium hydroxide cluster. In chapter 3, doping Er³⁺ ion into CuₓSe nanoparticles for the purpose of making efficient optical up-conversion materials is discussed. Er³⁺ ion was successfully doped into CuₓSe nanoparticles. However no up-conversion luminescence was detected, possibly due to the in-direct bandgap nature of CuₓSe. Chapter 4 discuses attaching CuxSe nanoparticles on the surface of NaYF₄:Gd, Er,Yb nanorod. The purpose is to increase up-conversion efficiency of NaYF₄:Gd, Er,Yb nanorod through surface plasmon resonance enhancement property of CuₓSe nanoparticle. The CuₓSe nanoparticles were successfully attached onto NaYF₄:Gd, Er,Yb nanorod surface through exposing the suspension containing CuₓSe nanoparticles and NaYF₄:Gd, Er,Yb nanorods to UV irradiation. The up-conversion efficiency of NaYF₄:Gd, Er,Yb nanorods was increased after CuₓSe nanoparticle attachment. Chapter 5 discussed the synthesis and characterization of functional Ln(BDC)(1.5)∙DMF (Ln = Eu, Tb, Gd) metal-organic frameworks (MOFs). The absence of OH group containing species within this MOF rendered them ideal substrates as luminescent material because luminescence quenching caused by OH groups could be avoided. A series of MOF with luminescent color ranging from red, orange, yellow and green were obtained by adjusting the relative Eu and Tb content in the MOF lattice. The magnetocaloric effect of Gd(BDC)1.5∙DMF was also studied. Chapter 6 discussed doping Co²⁺ ion into pyrochlore-like Zn(INA)₂ (INA = isonicotinate) MOF lattice for the purpose of making magnetically active pyrochlore-like MOF structures. The highest Co²⁺ doping concentration of 57% was successfully achieved. However, no significant magnetic frustration was observed, possibly due to the far separation between doped Co²⁺ ions. Chapter 7 discussed the etching of Zn(INA)₂ MOF crystal to increase microporous exposure. When Zn(INA)₂ MOF crystals were immersed in Co(NO₃)₂∙6H₂O acetonitrile solution, defined effective etching, which could effectively increase microporous exposure, took place. When Zn(INA)₂ MOF crystals were immersed in Co(NO₃)₂∙6H₂O N,N-dimethylformamide solution, defined ineffective etching, which could not increase microporous exposure, took place dominantly. Increasing etching temperature resulted in similar but more severe etching. However, new cobalt dominant MOF phases formed when etching was performed under elevated temperature.
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Brozell, Scott Raymond. "Spin-orbit configuration interaction calculations of Actinide and Lanthanide Systems /." The Ohio State University, 1999. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488192447429836.
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Martin, Noreen. "Azacryptand hosts for transition, main group and lanthanide cations." Thesis, Queen's University Belfast, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318842.
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Bell, Zoe Rachel. "Lanthanide and copper complexes of new multidentate encapsulating ligands." Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324327.
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Davies, Dita. "Design of shell-type ligands for luminescent lanthanide complexes." Thesis, University of Birmingham, 2011. http://etheses.bham.ac.uk//id/eprint/1742/.
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A series of lanthanide complexes based on tetraphenyl imidodiphosphate ligand have been prepared in order to investigate the ligand ability to act as a sensitiser for f-f based luminescence for the visible and NIR emitting ions. Furthermore, novel bimetallic luminescent lanthanide complexes based on two imidodiphosphate binding sites have been prepared for the examination of dinuclear lanthanide complexes formation. The sensitising properties of the bistpOp have been investigated by luminescence spectroscopy. A new ligand based on biphenyl sensitisers has been developed utilising an imidodiphosphate binding site. The lanthanide complexes have been prepared and their photophysical properties analysed.
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Breeze, Matthew I. "Crystallisation and characterisation of bimetallic- and lanthanide- organic frameworks." Thesis, University of Warwick, 2014. http://wrap.warwick.ac.uk/67088/.
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Several new mixed-metal analogues of MIL-53 have been synthesised using iron and vanadium. The properties of the mixed-metal materials are affected greatly by the ratio of the two metals. Analysis of the EXAFS spectra of a mixed-metal MIL-53(Fe, Cr) sample was performed supporting the homogeneity of the material. The investigation of mixed ironcobalt materials was also studied. Several new lanthanide-organic frameworks are described. Through mediation of the reaction solvent and subsequent calcinations, several new ytterbium-organic frameworks have been synthesised and their properties investigated. Using a solvent mixture of between 1:0 and 6:4 DMF to water leads to the formation of MB2, [Yb2(BDC)3(DMF)2]∙2H2O, which contains ytterbium-carboxylate chains. Calcination of MB2 creates Yb2(BDC)3, a material that exhibits permanent porosity. Further decreasing the DMF to water ratio in synthesis leads to the formation of MB3, [Yb2(BDC)3(DMF)2(H2O)2], which contains ytterbium-carboxylate dimers. Although sharing similar chemical formulae, MB2 and MB3 vary greatly in terms of structure and properties. Despite of this, both MB2 and MB3 can be calcined into the same Yb2(BDC)3 material, seen from the calcination of MB2. Attempts to create analogues of MB2 and MB3 using other lanthanides were unsuccessful with the exception of lutetium. In spite of this, doping of MB2(Yb) with other lanthanides was successful and their luminescence properties studies. Synthesis of isoreticular analogues of MB2 and MB3 were partially successful with an isoreticular analogue of MB3, MB5, being formed. Crystallisation of several metal-organic frameworks were followed using both ex situ and in situ methods and it was shown these two sets of techniques can complement one another to enable the pathways of MOF formation to be monitored.
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Knoche, Krysti Lynn. "Density gradient films, lanthanide electrochemistry, and magnetic field effects on hydrogen evolution, oxygen reduction, and lanthanide electrochemistry." Diss., University of Iowa, 2015. https://ir.uiowa.edu/etd/3124.
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Electroanalytical techniques are used to investigate mass transport through density gradient films; lanthanide triflate reduction and oxidation in a Nafion/acetonitrile matrix; and magnetic field effects on hydrogen evolution reaction (HER), oxygen reduction reaction (ORR), and lanthanide electrochemistry.
Graded density films are more dense at the electrode surface and become less dense out into solution due to a brush polymer structure. Fick's second law expands to account for a diffusion coefficient that varies with distance x normal to the electrode surface. Confocal microscopy, cyclic voltammetry, and computer simulations are used to investigate density graded Ficoll® films. Mass transport approaches steady state (scan rate independence) at slow scan rates where the diffusion length samples the entire film. The use of Ficoll to template an ion exchange polymer is explored by casting Nafion® Ficoll composites.
Lanthanide electrochemistry is enabled in acetonitrile at a Nafion modified platinum electrode in the presence of triflate ligands. Formal potentials are shifted into the voltage window of acetonitrile accessible due to triflate complexation. The Nafion further solubilizes the compounds. The mechanism (ECEC) is studied with cyclic voltammetry and x-ray photoelectron spectroscopy.
Magnetic field effects on electrochemical systems have been of interest to researchers for the past 65 years. Mass transport effects, such as magnetohydrodynamics and magnetic field gradient effects have been reported, but the Leddy group focuses on electron transfer effects. Electrode surfaces are modified with composite films of magnetic microparticles suspended in ion exchange polymer Nafion. Effects are verified to be electron transfer related and due to the magnetization of chemically inert microparticles. The magnets catalyze the rates of important electron transfer reactions such as hydrogen evolution and oxygen reduction.
Magnetic field effects on HER at various noncatalytic metal electrodes are explored with linear scan voltammetry. There is a correlation between the magnetic susceptibility of the electrode metals and the HER exchange currents (reaction rates). Exchange currents are 103× larger for a paramagnetic metal electrode than a diamagnetic one with the same work function. The overpotential at diamagnetic electrodes is decreased by modification with a Nafion + magnetic microparticle composite film. A decrease in overpotential of ∼70 % for all electrodes except platinum is observed. The overpotential decrease correlates with the magnetic susceptibility of the particles.
Magnets can enhance differences between lanthanide cyclic voltammograms by shifting current densities at a given potential and enhancing current based on the number of 4f electrons and magnetic moment of each lanthanide ion.
Magnetic field effects on ORR in acetonitrile are investigated with cyclic voltammetry. In aprotic solvents, ORR proceeds by a one electron transfer reaction to paramagnetic O2.–. Enhanced reversibility and electron transfer kinetics are observed as well as a decrease in overpotential of ∼100 mV. Magnetic field effects on ORR in a lanthanide triflate solution are also examined. Electron transfer kinetics and reversibility are further enhanced in the presence of lanthanide triflate.
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Thom, James Andrew. "Self-assembly and anion recognition with binuclear lanthanide complexes." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:20de876d-0a52-4f11-82b7-922fc3e2ee45.
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This work describes an investigation into the solution-phase binding of anionic guests by bimacrocyclic lanthanide complexes. It outlines the preparation of different classes of complexes bearing two metallic domains, and the effects of association on both the complex and the guest. Chapter one provides a cursory introduction to the fundamental properties of the lanthanides with a focus on luminescence. A brief literature review is given on the use of emissive lanthanide probes for the sensing of analytes. Chapter two concerns the preparation and properties of a series of binuclear complexes in which the two centres are linked with a short spacer group, with the aim of selectively sequestering small anions such as the halides in solution. The concept of luminescence titration will be introduced and then used to assess the binding parameters of a selection of guests. Chapter three describes a related class of ditopic lanthanide complexes in which the two metal centres are separated by a semi-rigid butyne linking group. Luminescence studies are again used to evaluate the binding constants of homologous series of dianions to ascertain how the size, geometry and functionalization of the anionic guest impacts on binding. Chapter four explores the coordination of phosphate species and assesses the ability to bind biologically significant phosphates of some of the complexes from Chapter 3. Chapter five details an investigation into the effects on guest-selectivity of further lengthening the linking unit which separates the two macrocyclic binding domains. Chapter six summarises the work done throughout the thesis and draws some overarching conclusions, as well as highlighting areas for further study. Chapter seven describes the experimental procedures.
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Watt, Fabian Allan [Verfasser]. "Synthesis and reactivity of anilidophosphine-supported lanthanide complexes : access to rare phosphorus-containing ligands in lanthanide coordination chemistry / Fabian Allan Watt." Paderborn : Universitätsbibliothek, 2021. http://nbn-resolving.de/urn:nbn:de:hbz:466:2-39619.
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Rouse, Jessica. "Synthesis and characterisation of lanthanide and other inorganic framework materials." Thesis, University of Southampton, 2010. https://eprints.soton.ac.uk/173801/.
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Five new cerium (IV) fluoride and fluoride–arsenate framework structures have been synthesised through hydrothermal techniques using CeF4 as a fluoride source. Cs[CeIV2F8[F.H2O]] (I) consists of layers, formed from linked Ce(F,O)n polyhedra cross-linked by hydrogen bonding that defines channels containing the caesium ions. [(NH4)5(H2O)2][CeIV4(AsO4)6(H2O)F3] (II), has an open framework structure with large channels filled with NH4+ cations and H2O molecules. CeIV[AsO4]F (III) and CeIV[AsO4]F[H2O] (IV) exhibit two types of bridging (Ce–O–Ce and Ce–F–Ce) bonds between Ce(O,F)n polyhedra, and (NH4)[CeIVF2(AsO4)] (V), is isostructural with the previously reported fluoride-phosphate (NH4)[CeIVF2(PO4)]. The use of metal tetra-fluorides (MF4; M = Zr, Hf) in hydrothermal reactions, has led to the production of new structures that incorporate either phosphate or arsenate oxotetrahedra linking metal oxo-fluoro polyhedra. This new synthetic pathway has provided a safer route to formation that does not require the addition of the dangerous HF reagent. Seven new zirconium and four hafnium arsenate or phosphate materials have been identified including ZrIV(HAsO4)(AsO4)(NH4) (VI) a three-dimensional framework with NH4+ within the channels, ZrIV(AsO4)F(H2O) (VII) exhibits Zr-F-Zr linkages, ZrIV(HAsO4)2 a novel three-dimensional framework (VIII) and ZrIV2(AsO4)3(NH4)(H2O) (IX) analogous to the mineral Langbeinite. Organic amines included in the reaction mixture can template the frameworks and form cavities, as observed within the channels of HfIV2F(HAsO4)(AsO4)2[Temp-Hn]1/n(H2O)1.5 (XIII) (Temp = ethylenediamine/diethylenetriamine). The substitution of fluoride ions for oxygen in the metal polyhedral unit has produced variations in the dimensionality of the materials formed as fluoride is more frequently incorporated as terminating species, reducing framework dimensionality. The controlled addition of these fluoride species, has provided a route to the rational design of one, two and three-dimensional framework structures. Hexagonal lanthanide phosphates (LnIIIPO4.nH2O) with the mineral Rhabdophane structure type were synthesised through hydrothermal techniques and analysed upon heating where a distinct increase in the a-axis lattice length was observed upon dehydration of the structure. Variable-temperature X-ray diffraction, EDX, TGA and fluorescence studies were undertaken to illustrate the interaction between the lanthanide cations and the water molecules that reside within the channels of the framework.
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Khandelwal, Amit Harikant. "Lithium, sodium and lanthanide metal inorganic and organic salt complexes." Thesis, University of Cambridge, 1994. https://www.repository.cam.ac.uk/handle/1810/272664.
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Williams, Daniel M. "Phosphate ester hydrolysis promoted by lanthanide (III) and transition metal complexes." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=35551.
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Phosphate ester linkages are omnipresent in nature and are found in many biologically important molecules such as DNA, RNA and ATP. Many enzymes that hydrolyze phosphate esters are activated by metal ions. Since the structure of biological enzymes can be quite complicated, it is often useful to work with simpler artificial metalloenzymes to help elucidate the mechanisms by which phosphate ester hydrolysis is activated by metals.In principle, simple dinuclear metal complexes could hydrolyze phosphate esters by double Lewis acid activation or by a combination of single Lewis acid activation and metal-hydroxide activation. These two mechanisms are kinetically indistinguishable. In this study, two different phosphate substrates are used to distinguish these mechanisms.
Lanthanide (iii) salts have proven extraordinarily effective in accelerating the rate of phosphate ester hydrolysis by several orders of magnitude. Consequently, there has been much effort in recent years to develop a ligand that would bind lanthanides so as to further improve their ability to hydrolyze phosphates. These efforts have met with limited success. Reported here is a dinuclear lanthanide (iii) complex which hydrolyzes BNPP (bis p-nitrophenyl phosphate) with unprecedented reactivity at pH 7.0 and 25°C.
A mononuclear copper (ii) 6,6'-diamino-2,2 '-bipyridyl complex is synthesized which gives one of the fastest rate accelerations reported for hydrolyzing 2',3 '-cAMP. A hydrogen bonding mechanism is proposed for the acceleration of the rate of hydrolysis of the cyclic phosphate.
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Saines, Paul James. "Structural Studies of Lanthanide Double Perovskites." Thesis, The University of Sydney, 2008. http://hdl.handle.net/2123/3939.
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This project focuses on the examination of the structures of lanthanide containing double perovskites of the type Ba2LnB'O6-d (Ln = lanthanide or Y3+ and B' = Nb5+, Ta5+, Sb5+ and/or Sn4+) using synchrotron X-ray and neutron powder diffraction. The first part of this project examined the relative stability of R3 rhombohedral and I4/m tetragonal structures as the intermediate phase adopted by the series Ba2LnB'O6 (Ln = lanthanide (III) or Y3+ and B' = Nb5+, Ta5+ or Sb5+). It was found that I4/m tetragonal symmetry was favoured when B' was a transition metal with a small number of d electrons, such as Nb5+ or Ta5+. This is due to the presence of p-bonding in these compounds. In the Ba2LnNbO6 and Ba2LnTaO6 series R3 rhombohedral symmetry was, however, favoured over I4/m tetragonal symmetry when Ln = La3+ or Pr3+ due to the larger ionic radius of these cations. The incompatibility of the d0 and d10 B'-site cations in this family of compounds was indicated by significant regions of phase segregation in the two series Ba2Eu1-xPrxNb1-xSbxO6 and Ba2NdNb1-xSbxO6. In the second part of this project the compounds in the series Ba2LnSnxB'1-xO6-d (Ln = Pr, Nd or Tb and B' = Nb5+ or Sb5+) were examined to understand the relative stability of oxygen vacancies in these materials compared to the oxidation of the lanthanide cations and to determine if any oxygen vacancy ordering occurred. It was found, using a combination of structural characterisation, X ray Absorption Near Edge Structure and Ultra-Violet, Visible and Near Infrared spectroscopies, that with Ln = Pr or Tb increased Sn4+ doping results in a change in the oxidation state of the Ln3+ cations to Ln4+. This leads to those series containing little or no oxygen vacancies. A loss of B site cation ordering was found to accompany this oxidation state change and phase segregation was found to occur in the Ba2PrSnxSb1-xO6-d series most likely due to the Pr3+ and Pr4+ cations segregating into different phases. The Nd3+ cations in the series Ba2NdSnxSb1-xO6-d, however, can not oxidise to the tetravalent state so the number of oxygen vacancies rises with increasing x. It was found that oxygen vacancies concentrate onto the axial site of the compounds with x = 0.6 and 0.8 at ambient temperature. In Ba2Sn0.6Sb0.4O5.7 the oxygen vacancies were found to change to concentrating on the equatorial site at higher temperatures and it is suggested that this oxygen vacancy ordering plays a role in the adoption of I2/m monoclinic symmetry.
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Saines, Paul James. "Structural Studies of Lanthanide Double Perovskites." Faculty of Science. School of Chemistry, 2008. http://hdl.handle.net/2123/3939.
Full textAbstract:
Doctor of Philosophy(PhD)This project focuses on the examination of the structures of lanthanide containing double perovskites of the type Ba2LnB'O6-d (Ln = lanthanide or Y3+ and B' = Nb5+, Ta5+, Sb5+ and/or Sn4+) using synchrotron X-ray and neutron powder diffraction. The first part of this project examined the relative stability of R3 rhombohedral and I4/m tetragonal structures as the intermediate phase adopted by the series Ba2LnB'O6 (Ln = lanthanide (III) or Y3+ and B' = Nb5+, Ta5+ or Sb5+). It was found that I4/m tetragonal symmetry was favoured when B' was a transition metal with a small number of d electrons, such as Nb5+ or Ta5+. This is due to the presence of p-bonding in these compounds. In the Ba2LnNbO6 and Ba2LnTaO6 series R3 rhombohedral symmetry was, however, favoured over I4/m tetragonal symmetry when Ln = La3+ or Pr3+ due to the larger ionic radius of these cations. The incompatibility of the d0 and d10 B'-site cations in this family of compounds was indicated by significant regions of phase segregation in the two series Ba2Eu1-xPrxNb1-xSbxO6 and Ba2NdNb1-xSbxO6. In the second part of this project the compounds in the series Ba2LnSnxB'1-xO6-d (Ln = Pr, Nd or Tb and B' = Nb5+ or Sb5+) were examined to understand the relative stability of oxygen vacancies in these materials compared to the oxidation of the lanthanide cations and to determine if any oxygen vacancy ordering occurred. It was found, using a combination of structural characterisation, X ray Absorption Near Edge Structure and Ultra-Violet, Visible and Near Infrared spectroscopies, that with Ln = Pr or Tb increased Sn4+ doping results in a change in the oxidation state of the Ln3+ cations to Ln4+. This leads to those series containing little or no oxygen vacancies. A loss of B site cation ordering was found to accompany this oxidation state change and phase segregation was found to occur in the Ba2PrSnxSb1-xO6-d series most likely due to the Pr3+ and Pr4+ cations segregating into different phases. The Nd3+ cations in the series Ba2NdSnxSb1-xO6-d, however, can not oxidise to the tetravalent state so the number of oxygen vacancies rises with increasing x. It was found that oxygen vacancies concentrate onto the axial site of the compounds with x = 0.6 and 0.8 at ambient temperature. In Ba2Sn0.6Sb0.4O5.7 the oxygen vacancies were found to change to concentrating on the equatorial site at higher temperatures and it is suggested that this oxygen vacancy ordering plays a role in the adoption of I2/m monoclinic symmetry.
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Sweet, Lucas Edward. "Synthesis, structure and magnetic properties of lanthanide cluster compounds." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-3128.
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Dwyer, Jennifer Lisa Mary. "Alkali metal lanthanide binaphtholates and their use in enantioselective alkylation reactions." Thesis, University of Liverpool, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250273.
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Berwick, Matthew Robert. "The de novo design of lanthanide coiled coils for imaging applications." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6452/.
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This thesis describes the design, synthesis and evaluation of a series of \(de\) \(novo\) designed peptide sequences for lanthanide binding, with the aim of creating a new class of imaging agents for luminescence and magnetic resonance imaging, due to the potential of controlling the complexes water coordination and rotational correlation time. The peptides were designed to form trimeric coiled coil motifs, with a lanthanide binding site incorporated inside the hydrophobic core. This binding site was generated using solely naturally occurring amino acids and was found to be specific for lanthanides over other biologically relevant metals. A 10 Å translation of the binding site, throughout the peptide sequence, was shown to influence the coiled coil stability and metal coordination, with the amino acids in the central binding sites saturating the lanthanide coordination. Whereas, when the binding site was located at the extremities of the peptide sequence, not all of the donor ligands were required, resulting in the presence of up to three exogenous water molecules. Ultimately, this had profound effects on the relaxivity of the complexes, with a four-fold variation in the transverse relaxivity observed, but importantly all designed peptides displayed an increase in relaxivity compared to current MRI contrast agents.
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Mihalcea, Ionut. "Crystal chemistry of coordination polymers based on uranyl and mixed uranyl - lanthanide carboxylates." Thesis, Lille 1, 2012. http://www.theses.fr/2012LIL10119/document.
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Ce travail de thèse décrit la synthèse, l’étude cristallochimique et le comportement thermique de polymères de coordination à base de cations uranyle, ou mixtes uranyle-lanthanide complexés par des ligands carboxylates aromatiques (acide phthalique et dérivés). L’emploi de 7 molécules polycarboxylates a conduit à la formation de plus de 25 nouveaux composés type Uranyl-Organic Framework (UOF) ou hybrides uranyle-organique, ou encore mixtes uranyle-lanthanide-organique. Certains de ces ligands on montré une grande diversité d’arrangements atomiques, avec par exemple, l’isophthalate qui conduit à la formation de 10 complexes de coordination, alors que d’autres (par exemple terephthalate) ont permis d’isoler un seul type d’assemblage. Certaines de ces phases contiennent classiquement des briques de construction inorganiques monomériques ou tétramériques alors que d’autres mettent en évidence des blocs trimériques linéaires ou octamériques originals, ou encore des systèmes de chaînes inorganiques générant des structures à tunnels inédits. Une configuration rare d’interaction cation-cation (CCI ou U=O-U) a été également identifiée dans l’isophthalate à base d’unité octamérique. La synthèse de toutes ces phases a permis une meilleure compréhension des réactions hydrothermales et de l’influence de différents paramètres influant la formation du produit final. Pour les phases obtenues sous formes pures, les comportements thermiques et leur stabilité ont été étudiés. Ces expériences ont permis d’établir des relations entre le précurseur initial, la dégradation thermique et les conditions de formation de l’oxyde final. Les spectres de fluorescence ont été collectés et indiquent des informations sur l’influence de la nature du ligand organique ou du type du motif de construction inorganiqueThis thesis work concerns the synthesis, crystal structural study and thermal behavior of coordination polymers type uranyl and mixed uranyl-lanthanide aromatic carboxylates. Using a series of 7 aromatic carboxylate ligands, more than 25 new uranyl (so-called Uranyl-Organic Framework or UOF) and mixed uranyl-lanthanide coordination polymers have been synthesized and described in this manuscript. Some of the ligands have proven to be very prolific such as the isophthalic acid, which is present in 10 coordination polymers and with others (such as terephthalic acid) only one complex could be isolated. Some of the obtained phases contain typical monomeric or tetrameric SBUs and others possess unique features such as octanuclear SBU with an edge sharing CCI (U=O-U), linear trinuclear SBU or polymeric SBU delimiting large tunnel systems. The synthesis of all these phases conducted to a better understanding of the hydrothermal reactions and the influence of different parameters over the final reaction product. For each of the phases obtained pure the thermal behavior and thermal stability have been studied. These experiments offer a better understanding of the relation between the structure of the initial complex, the thermal degradation conditions and the nature of final oxide. Also for these phases the fluorescence emission spectra were recorded, offering information about the influence of different ligands or different type of SBUs over the typical uranyl spectrum
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Scarpantonio, Luca. "Studies of DNA binding of lanthanide platinum complexes." Thesis, University of Birmingham, 2011. http://etheses.bham.ac.uk//id/eprint/2860/.
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Using supramolecular principles, we have been designing luminescent lanthanide complexes with a defined hairpin bis-interlacator in order to obtain luminescent probes able to recognise DNA. The complexes are comprised of Platinum(II) terpyridine, which acts as a DNA recognition site and is brought together with a "remote" luminescent lanthanide unit. All the synthetic approaches were based on the accessibility of the lanthanide-platinum complexes by the self-assembly of different components in a one pot reaction. Thus, we have been able to isolate a water soluble heterometallic complex based on thiophenal linkage named [LnPt\(_2\)]Cl\(_2\). The complex has a relatively weak lanthanide luminescence, which increases upon addition of DNA. Photophysical and DNA binding properties of the lanthanide-platinum complex were investigated by UV-vis absorption, luminescent studies and circular and linear dichroism. Oligonucleotides of twelve bases were also used to investigate the intercalation [LnPt\(_2\)]Cl\(_2\) and the mono-intercalator AATP used as control compound. Using bidimensional NMR techniques, we investigated the binding site for [LnPt\(_2\)]Cl\(_2\) and AATP upon interaction with Dickerson-Drew sequence. The sulphur lanthanide-platinum linkage in [LnPt\(_2\)]Cl\(_2\) was replaced with an acetylide one in order to introduce new photophysical features. Thus the self-assembly procedures based on DTPA-bis(amido-acetylide) and a platinum(II) terpyridine led us to isolate a new lanthanide-platinum complex named [LnC\(\equiv\)CPt\(_2\)] (CH\(_3\)SO\(_3\))\(_2\). The photophysical properties and the DNA binding properties toward interaction with CT-DNA were investigated. The complex named LnC\(\equiv\)CPt\(_2\)](CH\(_3\)S)\(_3\))\(_2\) exhibited a relatively strong lanthanide luminescence that increased upon addition of DNA. The bi-functional metal complex [EuLPt](PF\(_6\)) (where Pt=platinum-2,2':6'2"-terpyridine and L=assymmetric DTPA bisamide ligand with a thiopheno pendant arm and a quinoline moiety) was synthesised and the interaction of [EuLPt](PF\(_6\)) with CT-DNA was examined by luminescence spectroscopy, linear and circular dichroism studies and thermal denaturation studies. The [EuLPt](PF\(_6\)) retained the ability to increase its luminescence upon the addition of CT-DNA. The binding properties of the complexes were tested toward interaction with plasmid DNA by gel electrophoresis and properties such as the unwinding angle were measured. The bis-intercalators [LnPt\(_2\)]Cl\(_2\) and [LnC\(\equiv\)CPt\(_2\)](CH\(_3\)SO\(_3\))\(_2\) showed the ability to uncoil DNA almost as well as cisplatin and at low concentrations, while almost double the amount of mono-intercalators, such as [EuLPt](PF\(_6\)) is required to observe the same uncoiling effect.
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Duncalf, David J. "The synthesis and reactivity of some lanthanide alkoxide, siloxide and silyl derivatives." Thesis, University of Sussex, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239605.
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Slope, Louise Nicola. "Selective lanthanide binding sites engineered within a de novo designed coiled coil." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7971/.
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De novo designed coiled coils are described that are capable of selectively discriminating between Ln3+ ions. Sites buried within the hydrophobic core are able to actively discriminate against both larger and smaller ions. Whereas linearly translating the binding site towards the N-terminus, ‘turns-off’ selectivity, owing to N-terminal fraying and flexibility. Mutating first sphere coordinating and second sphere non-coordinating residues was found to impact on the metal coordination chemistry, including the hydration state of the bound Tb3+, which in turn led to altered metal selectivity and MRI relaxivities of the Gd3+ complexes. Given these findings, a novel two binding site coiled coil trimer was designed in which incorporation of both a ‘buried’ and N-terminal site enabled two different Ln3+ ions with differing properties to be bound within a single system. This dual lanthanide binding construct resembles a significant development within the field, being the first example established in a peptide assembly, and is notably even capable of selectively binding and discriminating between two different, but similar, Ln3+ ions. Translating the second Ln3+ binding site linearly along the coiled coil resulted in a series of dual Ln3+ binding peptides in which the distance between the metal ions can be controlled.
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Savage, Alison Clare. "Controlled coating of nanoparticles with peptides and lanthanide complexes : a photophysical evaluation." Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/4958/.
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This thesis describes the co-coating of gold nanoparticles with different combinations of lanthanide complexes and peptides, and the effect of this co-coating on the photophysical properties of the lanthanide complexes has been examined. A photophysical study of europium (III) ions binding to two surface active peptides in solution is presented and the ability of these peptides to bind the europium ions whilst tethered to gold nanoparticles is discussed. Lanthanide complexes with a diethylenetriaminepentaacetic acid (DTPA) binding motif were prepared and attached to gold nanoparticles with different peptides to investigate their photophysical properties and their potential as a cellular imaging agent has been demonstrated. The co-coating of gold nanoparticles with europium and gadolinium complexes is also introduced, and these nanoparticles have the potential to be used as a multi-modal imaging agent for luminescent and magnetic resonance imaging. The synthesis of an azo-dye has been undertaken and its ability to bind and sensitise the near infrared lanthanides neodymium (III) and ytterbium (III) has been demonstrated. It was found to form complexes with these lanthanides, and the high molar absorption coefficients in the visible region allows for excitation at wavelengths up to 500 nm.
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Khan, Suleman Manawar. "Surface active lanthanide complexes for sensing applications on silica and gold surfaces." Thesis, University of Birmingham, 2015. http://etheses.bham.ac.uk//id/eprint/5726/.
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The work presented in this thesis investigates the use of new luminescent lanthanide bis-amide DTPA complexes, both in solution and bound to gold and silica surfaces. The bis-amide arms have been modified with surface attachment groups consisting of disulphides, thioacetates and silyl ethers. Both sensitising and non-sensitising bisamides arms were attached to DTPA in order to develop the best lanthanide based sensor. When these visible and NIR emitting lanthanide complexes are bound to the surface they can be used to detect various small analytesm including benzoic acid, phthalic acid, isophthalic acid, picolinic acid, dipicolinic acid, quinaldic acid, dibenzoyl methane and curcumin. The detection of analytes was performed on surfaces and in solution allowing for comparisons between the two techniques to be made. Lanthanide complexes were attached to silica microparticles and they were used for detection of analytes under flow conditions; these studies were compared to surface and solution analyte detection. The lanthanide-based silica microparticles were developed further to show the advantages of bimodal luminescent silica microparticles. The development of self-assembled monolayers of the lanthanide complexes on gold were studied using surface plasmon resonance and ellipsometry.
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Viswanathan, Subha. "Nitro- and oxazoline-derivatized antennas structural and photophysical characterization of their lanthanide complexes /." Related electronic resource:, 2007. http://proquest.umi.com/pqdweb?did=1362530571&sid=2&Fmt=2&clientId=3739&RQT=309&VName=PQD.
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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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Deng, Hai-Bin. "Synthesis and structural characterization of group 8-group 11 and group 8-lanthanide heterometallic complexes /." The Ohio State University, 1991. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487694389393723.
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Hammond, Stephen Peter. "Imaging of luminescent nanoparticles in flows : development of surface active luminescent lanthanide complexes." Thesis, University of Birmingham, 2009. http://etheses.bham.ac.uk//id/eprint/1235/.
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We have developed a new ligand (H\(_3\)L\(^2\)) based on a DTPA bis-amide backbone which improves upon previous work within the group. The quantum yields of the europium and samarium complexes of H\(_3\)L\(^2\) are greatly enhanced over that of H\(_3\)L\(^1\). The previously observed nanoparticle-based quenching of the lanthanide luminescence lifetime of EuL\(^1\) is suppressed in EuL\(^2\). We have demonstrated the functionalisation of gold and platinum nanoparticles of various sizes with the surface active lanthanide complexes of H\(_3\)L\(^1\) and H\(_3\)L\(^2\). As a proof of principle, we have imaged, tracked and measured velocities of individual EuL\(^2\) functionalised nanoparticles in an aqueous flow, providing flow-rates accurate to micrometer resolution of fluids through a 2 mm diameter tube. We have also observed the microscale mixing of a nanoparticle labelled solution with water on time-scales of milliseconds to seconds. We can study the development and measure the dimensions of features present during mixing and therefore assess the efficiency of that mixing. We have also visualised a turn-on event at the boundary of aqueous solutions of Eu(III) ions and H\(_3\)L\(^2\)-functionalised nanoparticles during mixing, demonstrating a novel optical method for ascertaining the degree of mixing between two solutions and the position and area of that mixing.
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Stacey, Oliver J. "Novel luminescent platinum (II) and lanthanide (III) complexes towards imaging, diagnostics and therapeutics." Thesis, Cardiff University, 2015. http://orca.cf.ac.uk/73204/.
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This thesis discusses the development and synthesis of ligands for coordination to dand f- block metal ions. The subsequent coordination chemistry to PtII and a range of LnIII metal ions is outlined, along with the photophysical properties of the resultant compounds towards bimodal imaging agents and probes for diagnostic and therapeutic applications. Chapter 2 presents the synthesis and characterisation of a range of PtII complexes using functionalised 2-phenylquinoline ligands. A range of products were synthesised by utilising a variety of ancillary ligands, including β-diketones, 8-hydroxyquinoline, 2,2′-bipyridine and pyridine, in order to investigate any effects on the photophysical properties. X-ray crystallography confirmed the anticipated structures of several compounds whilst 195Pt NMR was employed to probe the metal environment in the different complexes. Chapter 3 builds on the investigations in the previous chapter by altering the functionality of the 2-phenylquinoline ligand in order to tune the solubility. The second part of Chapter 3 exploits the facile coordination of pyridine, as found in Chapter 2, by introducing pendant pyridine-appended macrocycles encapsulating LnIII ions. This provided bimetallic complexes with good water solubility, which allowed relaxivity measurements to be carried out. Photophysical measurements also gave evidence of direct sensitisation of the LnIII ion by PtII based 3MLCT emission. Chapter 4 extends the 2-phenylquinoline functionality to incorporate naphthyl, anthracenyl and pyrenyl chromophores with suitable solubility in common organic solvents. The complexes were investigated to determine whether it was possible to observe interactions between the excited state of the chromophore and the metalcentred excited state. Low temperature and degassed steady state luminescence and lifetime measurements were obtained in order to build energy level diagrams to explain the interplay of excited states. Chapter 5 discusses the development of anthraquinone-based polypyridyl ligand scaffolds for the incorporation of LnIII ions. The ligands possess subtle differences that result in changes in the coordination sphere of the LnIII ion. This was confirmed by determining the inner-sphere hydration of the LnIII ions through observing the luminescence properties of the complexes.