Journal articles: 'Lanthanide'

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Evans, William J., and David S. Lee. "Early developments in lanthanide-based dinitrogen reduction chemistry." Canadian Journal of Chemistry 83, no. 4 (April 1, 2005): 375–84. http://dx.doi.org/10.1139/v05-014.

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Although the first crystallographically characterized lanthanide dinitrogen complex was reported in 1988 with samarium, it is only in recent years that this field has expanded to include fully characterized examples for the entire series of lanthanides. The development of lanthanide dinitrogen chemistry has been aided by a series of unexpected results that present some good lessons in the development of science. This review presents a chronological account of the lanthanide dinitrogen chemistry discovered in our laboratory through the summer of 2004.Key words: lanthanides, dinitrogen, reduction, alkali metal, nitrogen fixation, diazenido.

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Werts, Martinus H. V. "Making sense of Lanthanide Luminescence." Science Progress 88, no. 2 (May 2005): 101–31. http://dx.doi.org/10.3184/003685005783238435.

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The luminescence of trivalent lanthanide ions has found applications in lighting, lasers, optical telecommunications, medical diagnostics, and various other fields. This introductory review presents the basics of organic and inorganic luminescent materials containing lanthanide ions, their applications, and some recent developments. After a brief history of the discovery, purification and early spectroscopic studies of the lanthanides, the radiative and nonradiative transitions of the 4f electrons in lanthanide ions are discussed. Lanthanide-doped phosphors, glasses and crystals as well as luminescent lanthanide complexes with organic ligands receive attention with respect to their preparation and their applications. Finally, two recent developments in the field of luminescent materials are addressed: near-infrared luminescent lanthanide complexes and lanthanide-doped nanoparticles.

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Lin, Ying-Ting, Rong-Xuan Liu, Gilbert Audira, Michael Edbert Suryanto, Marri Jmelou M. Roldan, Jiann-Shing Lee, Tzong-Rong Ger, and Chung-Der Hsiao. "Lanthanides Toxicity in Zebrafish Embryos Are Correlated to Their Atomic Number." Toxics 10, no. 6 (June 19, 2022): 336. http://dx.doi.org/10.3390/toxics10060336.

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Rare earth elements (REEs) are critical metallic materials with a broad application in industry and biomedicine. The exponential increase in REEs utilization might elevate the toxicity to aquatic animals if they are released into the water due to uncareful handling. The specific objective of our study is to explore comprehensively the critical factor of a model Lanthanide complex electronic structures for the acute toxicity of REEs based on utilizing zebrafish as a model animal. Based on the 96 h LC50 test, we found that the majority of light REEs display lower LC50 values (4.19–25.17 ppm) than heavy REEs (10.30–41.83 ppm); indicating that they are atomic number dependent. Later, linear regression analyses further show that the average carbon charge on the aromatic ring (aromatic Cavg charge) can be the most significant electronic structural factor responsible for the Lanthanides’ toxicity in zebrafish embryos. Our results confirm a very strong correlation of LC50 to Lanthanide’s atomic numbers (r = 0.72), Milliken charge (r = 0.70), and aromatic Cavg charge (r = −0.85). This most significant correlation suggests a possible toxicity mechanism that the Lanthanide cation’s capability to stably bind to the aromatic ring on the residue of targeted proteins via a covalent chelating bond. Instead, the increasing ionic bond character can reduce REEs’ toxicity. In addition, Lanthanide toxicity was also evaluated by observing the disruption of photo motor response (PMR) activity in zebrafish embryos. Our study provides the first in vivo evidence to demonstrate the correlation between an atomic number of Lanthanide ions and the Lanthanide toxicity to zebrafish embryos.

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Weißhoff, Hardy, Katharina Janek, Peter Henklein, Herbert Schumann, and Clemens Mügge. "Elution Behavior and Structural Characterization of N- and C-functionalized DOTA Complexes for the Labelling of Biomolecules." Zeitschrift für Naturforschung B 64, no. 10 (October 1, 2009): 1159–68. http://dx.doi.org/10.1515/znb-2009-1008.

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Two types of lanthanide complexes of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) for the labelling of biomolecules were investigated by HPLC, MS and NMR spectroscopy. The elution behavior of lanthanide complexes of N-functionalized DOTA [1,4,7,10-tetraazacyclododecane- 1,4,7-triacetic acid-10-maleimidoethylacetamide (nDOTA-Mal) and 1-{2-[4-(maleimido- N-propylacetamidobutyl)amino]-2-oxoethyl}-1,4,7,10-tetraazacyclododecane-4,7,10-triacetic acid (nDOTA-Bu-Mal)] and C-functionalized DOTA [2-{4-(maleimido-N-propylacetamido)benzyl}-1,4, 7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (cDOTA-Bnz-Mal) and 2-(4-isothiocyanatobenzyl)- 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (cDOTA-Bnz-NCS)] was compared. N-functionalized lanthanide DOTA complexes coelute as required for their use as ICAT-analogous reagents. The complexation of the C-functionalized DOTA with lanthanides results in two fractions separable by HPLC. Coelution is observed for the main fractions of the lanthanide complexes. The retention times of the minor fractions show a dependence on the ionic radii of the metal ions. MALDI spectra of lanthanide-DOTA-peptide conjugates including different monoisotopic lanthanides demonstrate the advantage of the mass variations for extensive peptide and protein investigations.

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Kovács, Eszter M., József Kónya, and Noémi M. Nagy. "Structural curiosities of lanthanide (Ln)-modified bentonites analyzed by radioanalytical methods." Journal of Radioanalytical and Nuclear Chemistry 322, no. 3 (September 19, 2019): 1747–54. http://dx.doi.org/10.1007/s10967-019-06765-6.

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Abstract The effects of pH and lanthanide (La, Y) concentration were investigated on the release of iron from Ca-bentonite crystal structure. XRF results revealed that during the Ca–H cation exchange procedure iron loss was not observed. In the case of lanthanide modifications, the pH has low influence, meanwhile the concentration of lanthanide has high influence on iron loss. Thus, high amount of trivalent lanthanides cause the structural iron release.

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Chu, Frances, and Mary E. Lidstrom. "XoxF Acts as the Predominant Methanol Dehydrogenase in the Type I Methanotroph Methylomicrobium buryatense." Journal of Bacteriology 198, no. 8 (February 8, 2016): 1317–25. http://dx.doi.org/10.1128/jb.00959-15.

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ABSTRACTMany methylotrophic taxa harbor two distinct methanol dehydrogenase (MDH) systems for oxidizing methanol to formaldehyde: the well-studied calcium-dependent MxaFI type and the more recently discovered lanthanide-containing XoxF type. MxaFI has traditionally been accepted as the major functional MDH in bacteria that contain both enzymes. However, in this study, we present evidence that, in a type I methanotroph,Methylomicrobium buryatense, XoxF is likely the primary functional MDH in the environment. The addition of lanthanides increasesxoxFexpression and greatly reducesmxaexpression, even under conditions in which calcium concentrations are almost 100-fold higher than lanthanide concentrations. Mutations in genes encoding the MDH enzymes validate our finding that XoxF is the major functional MDH, as XoxF mutants grow more poorly than MxaFI mutants under unfavorable culturing conditions. In addition, mutant and transcriptional analyses demonstrate that the lanthanide-dependent MDH switch operating in methanotrophs is mediated in part by the orphan response regulator MxaB, whose gene transcription is itself lanthanide responsive.IMPORTANCEAerobic methanotrophs, bacteria that oxidize methane for carbon and energy, require a methanol dehydrogenase enzyme to convert methanol into formaldehyde. The calcium-dependent enzyme MxaFI has been thought to primarily carry out methanol oxidation in methanotrophs. Recently, it was discovered that XoxF, a lanthanide-containing enzyme present in most methanotrophs, can also oxidize methanol. In a methanotroph with both MxaFI and XoxF, we demonstrate that lanthanides transcriptionally control genes encoding the two methanol dehydrogenases, in part by controlling expression of the response regulator MxaB. Lanthanides are abundant in the Earth's crust, and we demonstrate that micromolar amounts of lanthanides are sufficient to suppress MxaFI expression. Thus, we present evidence that XoxF acts as the predominant methanol dehydrogenase in a methanotroph.

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Lumpe, Henning, Arjan Pol, Huub J. M. Op den Camp, and Lena J. Daumann. "Impact of the lanthanide contraction on the activity of a lanthanide-dependent methanol dehydrogenase – a kinetic and DFT study." Dalton Transactions 47, no. 31 (2018): 10463–72. http://dx.doi.org/10.1039/c8dt01238e.

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Citron, Irvin M., Patrick M. Hanlon, and Stephen Arthur. "Ultraviolet Spectroscopic Determination of Five Lanthanide Elements without Prior Separation." Applied Spectroscopy 47, no. 6 (June 1993): 764–72. http://dx.doi.org/10.1366/0003702934067027.

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This investigation has resulted in an analytical method for the quantitative determination of total lanthanide concentration in aqueous solution by absorbance at 240 nm in the ultraviolet followed by quantitative determination of individual lanthanide ion concentrations by the use of concentration-responsive absorption peaks in the 190–235 nm region. The 240-nm peak is present and is proportional to concentration regardless of the ligand employed to complex the lanthanides (including H2O). The individual lanthanide/ligand peaks in the 190–235 nm region were selected on the basis of their separation from one another, their linearity of absorbance vs. concentration, and their statistical reliability based on replicate sample analyses. Lanthanides involved in this investigation were La+3, Nd+3, Eu+3, Ho+3, and Yb+3. Ligands ultimately selected for complexation were citrate for La+3, Nd+3, and Ho+3, and DTPA for Eu+3, Ho+3, and Yb+3. When large amounts of heavy metal ions were present, a modified method was developed with citrate as the only complexing ligand for all five lanthanides. The method here developed permits the analyses of lanthanide ions in aqueous solution without prior separation and involves the use of comparatively inexpensive instrumentation (UV absorption spectrophotometer).

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Savić, Aleksandar, Anna M. Kaczmarek, Rik Van Deun, and Kristof Van Hecke. "DNA Intercalating Near-Infrared Luminescent Lanthanide Complexes Containing Dipyrido[3,2-a:2′,3′-c]phenazine (dppz) Ligands: Synthesis, Crystal Structures, Stability, Luminescence Properties and CT-DNA Interaction." Molecules 25, no. 22 (November 13, 2020): 5309. http://dx.doi.org/10.3390/molecules25225309.

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In order to create near-infrared (NIR) luminescent lanthanide complexes suitable for DNA-interaction, novel lanthanide dppz complexes with general formula [Ln(NO3)3(dppz)2] (Ln = Nd3+, Er3+ and Yb3+; dppz = dipyrido[3,2-a:2′,3′-c]phenazine) were synthesized, characterized and their luminescence properties were investigated. In addition, analogous compounds with other lanthanide ions (Ln = Ce3+, Pr3+, Sm3+, Eu3+, Tb3+, Dy3+, Ho3+, Tm3+, Lu3+) were prepared. All complexes were characterized by IR spectroscopy and elemental analysis. Single-crystal X-ray diffraction analysis of the complexes (Ln = La3+, Ce3+, Pr3+, Nd3+, Eu3+, Er3+, Yb3+, Lu3+) showed that the lanthanide’s first coordination sphere can be described as a bicapped dodecahedron, made up of two bidentate dppz ligands and three bidentate-coordinating nitrate anions. Efficient energy transfer was observed from the dppz ligand to the lanthanide ion (Nd3+, Er3+ and Yb3+), while relatively high luminescence lifetimes were detected for these complexes. In their excitation spectra, the maximum of the strong broad band is located at around 385 nm and this wavelength was further used for excitation of the chosen complexes. In their emission spectra, the following characteristic NIR emission peaks were observed: for a) Nd3+: 4F3/2 → 4I9/2 (870.8 nm), 4F3/2 → 4I11/2 (1052.7 nm) and 4F3/2 → 4I13/2 (1334.5 nm); b) Er3+: 4I13/2 → 4I15/2 (1529.0 nm) c) Yb3+: 2F5/2 → 2F7/2 (977.6 nm). While its low triplet energy level is ideally suited for efficient sensitization of Nd3+ and Er3+, the dppz ligand is considered not favorable as a sensitizer for most of the visible emitting lanthanide ions, due to its low-lying triplet level, which is too low for the accepting levels of most visible emitting lanthanides. Furthermore, the DNA intercalation ability of the [Nd(NO3)3(dppz)2] complex with calf thymus DNA (CT-DNA) was confirmed using fluorescence spectroscopy.

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Pereira, Cláudia C. L., José M. Carretas, Bernardo Monteiro, and João P. Leal. "Luminescent Ln-Ionic Liquids beyond Europium." Molecules 26, no. 16 (August 10, 2021): 4834. http://dx.doi.org/10.3390/molecules26164834.

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Searching in the Web of Knowledge for “ionic liquids” AND “luminescence” AND “lanthanide”, around 260 entries can be found, of which a considerable number refer solely or primarily to europium (90%, ~234). Europium has been deemed the best lanthanide for luminescent applications, mainly due to its efficiency in sensitization, longest decay times, and the ability to use its luminescence spectra to probe the coordination geometry around the metal. The remaining lanthanides can also be of crucial importance due to their different colors, sensitivity, and capability as probes. In this manuscript, we intend to shed some light on the existing published work on the remaining lanthanides. In some cases, they appear in papers with europium, but frequently in a subordinate position, and in fewer cases then the main protagonist of the study. All of them will be assessed and presented in a concise manner; they will be divided into two main categories: lanthanide compounds dissolved in ionic liquids, and lanthanide-based ionic liquids. Finally, some analysis of future trends is carried out highlighting some future promising fields, such as ionogels.

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Раджабов, Е. А., and В. А. Козловский. "Перенос электрона между разнородными лантаноидами в кристаллах BaF-=SUB=-2-=/SUB=- --- II механизмы переноса." Физика твердого тела 61, no. 5 (2019): 888. http://dx.doi.org/10.21883/ftt.2019.05.47587.19f.

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The processes of electron transfer from a divalent lanthanide acceptor (Eu, Sm, Yb) to a trivalent lanthanide donor (Nd, Sm, Dy, Tm, Yb) and reverse thermal transfer are studied in barium fluoride crystals. Electron phototransfer at room temperatures is accompanied by a counter-movement of the charge-compensating interstitial fluorine. In the process of photobleaching at low temperatures, the divalent lanthanide donor turns out to be near the interstitial fluorine, which causes its 4f-5d absorption bands to shift to the red. The magnitude of the shift increases with decreasing size of the lanthanide in the series (Nd, Sm, Dy, Tm, Yb). Detailed mechanisms of photo and thermal electron transfer between heterogeneous lanthanides in BaF2 crystals are analyzed.

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Pałasz, A., and P. Czekaj. "Toxicological and cytophysiological aspects of lanthanides action." Acta Biochimica Polonica 47, no. 4 (December 31, 2000): 1107–14. http://dx.doi.org/10.18388/abp.2000_3963.

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Lanthanides, also called rare-earth elements, are an interesting group of 15 chemically active, mainly trivalent, f-electronic, silvery-white metals. In fact, lanthanides are not as rare as the name implies, except for promethium, a radioactive artificial element not found in nature. The mean concentrations of lanthanides in the earth's crust are comparable to those of life-important elements like iodine, cobalt and selenium. Many lanthanide compounds show particular magnetic, catalytic and optic properties, and that is why their technical applications are so extensive. Numerous industrial sources enable lanthanides to penetrate into the human body and therefore detailed toxicological studies of these metals are necessary. In the liver, gadolinium selectively inhibits secretion by Kupffer cells and it decreases cytochrome P450 activity in hepatocytes, thereby protecting liver cells against toxic products of xenobiotic biotransformation. Praseodymium ion (Pr3+) produces the same protective effect in liver tissue cultures. Cytophysiological effects of lanthanides appear to result from the similarity of their cationic radii to the size of Ca2+ ions. Trivalent lanthanide ions, especially La3+ and Gd3+, block different calcium channels in human and animal cells. Lanthanides can affect numerous enzymes: Dy3+ and La3+ block Ca2+-ATPase and Mg2+-ATPase, while Eu3+ and Tb3+ inhibit calcineurin. In neurons, lanthanide ions regulate the transport and release of synaptic transmitters and block some membrane receptors, e.g. GABA and glutamate receptors. It is likely that lanthanides significantly and uniquely affect biochemical pathways, thus altering physiological processes in the tissues of humans and animals.

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Trzesowska, Agata, Rafal Kruszynski, and Tadeusz J. Bartczak. "Bond-valence parameters of lanthanides." Acta Crystallographica Section B Structural Science 62, no. 5 (September 18, 2006): 745–53. http://dx.doi.org/10.1107/s0108768106016429.

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Ln—O and Ln—N bond-valence parameters have been computed in coordination complexes for lanthanides (Ln) at oxidation states other than +3 (CeIV, SmII, EuII and YbII). Moreover, Ln—Cl, Ln—S and Ln—C(π-bonded) bond-valence parameters are presented, as calculated for coordination compounds. In general, the bond-valence parameters decrease in the order Ln—O > Ln—C > Ln—N > Ln—Cl > Ln—S. It has been found that the values of bond-valence parameters decrease with increasing lanthanide atomic number for coordination compounds. As expected, the values of lanthanide–oxygen and lanthanide–nitrogen bond-valence parameters diminish with increasing lanthanide oxidation state. Several examples are given where the total valence of the lanthanide ion is apparently incorrectly assigned, as well as cases where bond-valence method calculations confirm the doubtful oxidation state assignment.

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Xu, Hengbin, Jiamiao Qu, Milin Zhang, Yongde Yan, Xin Sun, Yanghai Zheng, Min Qiu, and Li Liu. "The linear relationship derived from the deposition potential of Pb–Ln alloy and atomic radius." New Journal of Chemistry 42, no. 20 (2018): 16533–41. http://dx.doi.org/10.1039/c8nj03342k.

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Zheng, Yue, Jing Huang, Feng Zhao, and Ludmila Chistoserdova. "Physiological Effect of XoxG(4) on Lanthanide-Dependent Methanotrophy." mBio 9, no. 2 (March 27, 2018): e02430-17. http://dx.doi.org/10.1128/mbio.02430-17.

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ABSTRACTA recent surprising discovery of the activity of rare earth metals (lanthanides) as enzyme cofactors as well as transcriptional regulators has overturned the traditional assumption of biological inertia of these metals. However, so far, examples of such activities have been limited to alcohol dehydrogenases. Here we describe the physiological effects of a mutation inxoxG, a gene encoding a novel cytochrome, XoxG(4), and compare these to the effects of mutation in XoxF, a lanthanide-dependent methanol dehydrogenase, at the enzyme activity level and also at the community function level, usingMethylomonassp. strain LW13 as a model organism. Through comparative phenotypic characterization, we establish XoxG as the second protein directly involved in lanthanide-dependent metabolism, likely as a dedicated electron acceptor from XoxF. However, mutation in XoxG caused a phenotype that was dramatically different from the phenotype of the mutant in XoxF, suggesting a secondary function for this cytochrome, in metabolism of methane. We also purify XoxG(4) and demonstrate that this protein is a true cytochromec, based on the typical absorption spectra, and we demonstrate that XoxG can be directly reduced by a purified XoxF, supporting one of its proposed physiological functions. Overall, our data continue to suggest the complex nature of the interplay between the calcium-dependent and lanthanide-dependent alcohol oxidation systems, while they also suggest that addressing the roles of these alternative systems is essential at the enzyme and community function level, in addition to the gene transcription level.IMPORTANCEThe lanthanide-dependent biochemistry of living organisms remains a barely tapped area of knowledge. So far, only a handful of lanthanide-dependent alcohol dehydrogenases have been described, and their regulation by lanthanides has been demonstrated at the transcription level. Little information is available regarding the concentrations of lanthanides that could support sufficient enzymatic activities to support specific metabolisms, and so far, no other redox proteins involved in lanthanide-dependent methanotrophy have been demonstrated. The research presented here provides enzyme activity-level data on lanthanide-dependent methanotrophy in a model methanotroph. Additionally, we identify a second protein important for lanthanide-dependent metabolism in this organism, XoxG(4), a novel cytochrome. XoxG(4) appears to have multiple functions in methanotrophy, one function as an electron acceptor from XoxF and another function remaining unknown. On the basis of the dramatic phenotype of the XoxG(4) mutant, this function must be crucial for methanotrophy.

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Onghena, Bieke, Eleonora Papagni, Ernesto Rezende Souza, Dipanjan Banerjee, Koen Binnemans, and Tom Vander Hoogerstraete. "Speciation of lanthanide ions in the organic phase after extraction from nitrate media by basic extractants." RSC Advances 8, no. 56 (2018): 32044–54. http://dx.doi.org/10.1039/c8ra06712k.

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Nielsen, Lea Gundorff, Anne Kathrine R. Junker, and Thomas Just Sørensen. "Composed in the f-block: solution structure and function of kinetically inert lanthanide(iii) complexes." Dalton Transactions 47, no. 31 (2018): 10360–76. http://dx.doi.org/10.1039/c8dt01501e.

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Williams, Neil J., Chi-Linh Do-Thanh, Joseph J. Stankovich, Huimin Luo, and Sheng Dai. "Extraction of lanthanides using 1-hydroxy-6-N-octylcarboxamido-2(1H)-pyridinone as an extractant via competitive ligand complexations between aqueous and organic phases." RSC Advances 5, no. 129 (2015): 107054–57. http://dx.doi.org/10.1039/c5ra23443c.

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Pallares, Roger M., David Faulkner, Dahlia D. An, Solène Hébert, Alex Loguinov, Michael Proctor, Jonathan A. Villalobos, et al. "Genome-wide toxicogenomic study of the lanthanides sheds light on the selective toxicity mechanisms associated with critical materials." Proceedings of the National Academy of Sciences 118, no. 18 (April 26, 2021): e2025952118. http://dx.doi.org/10.1073/pnas.2025952118.

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Lanthanides are a series of critical elements widely used in multiple industries, such as optoelectronics and healthcare. Although initially considered to be of low toxicity, concerns have emerged during the last few decades over their impact on human health. The toxicological profile of these metals, however, has been incompletely characterized, with most studies to date solely focusing on one or two elements within the group. In the current study, we assessed potential toxicity mechanisms in the lanthanide series using a functional toxicogenomics approach in baker’s yeast, which shares many cellular pathways and functions with humans. We screened the homozygous deletion pool of 4,291 Saccharomyces cerevisiae strains with the lanthanides and identified both common and unique functional effects of these metals. Three very different trends were observed within the lanthanide series, where deletions of certain proteins on membranes and organelles had no effect on the cellular response to early lanthanides while inducing yeast sensitivity and resistance to middle and late lanthanides, respectively. Vesicle-mediated transport (primarily endocytosis) was highlighted by both gene ontology and pathway enrichment analyses as one of the main functions disturbed by the majority of the metals. Protein–protein network analysis indicated that yeast response to lanthanides relied on proteins that participate in regulatory paths used for calcium (and other biologically relevant cations), and lanthanide toxicity included disruption of biosynthetic pathways by enzyme inhibition. Last, multiple genes and proteins identified in the network analysis have human orthologs, suggesting that those may also be targeted by lanthanides in humans.

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Camp, Clément, Valentin Guidal, Biplab Biswas, Jacques Pécaut, Lionel Dubois, and Marinella Mazzanti. "Multielectron redox chemistry of lanthanide Schiff-base complexes." Chemical Science 3, no. 8 (2012): 2433–48. http://dx.doi.org/10.1039/c2sc20476b.

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Kusrini, Eny, Zakaria Jaka Bahari, Anwar Usman, Arif Rahman, and Eko Adi Prasetyanto. "Recovery of Lanthanides from Indonesian Low Grade Bauxite Using Oxalic Acid." Materials Science Forum 929 (August 2018): 171–76. http://dx.doi.org/10.4028/www.scientific.net/msf.929.171.

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The present work describes the extraction of lanthanide (rare earth elements, REE) from low grade bauxite using acid leaching method. The aim of this study is to obtain the best condition for extraction of lanthanides from low grade bauxite. The effect of different parameters such as temperatures and concentration of oxalic acid in leaching process were investigated. The content of La, Ce and Y elements were determined using ICP-OES. The experimental result shows that the efficiencies of lanthanide leaching are the temperature-dependent. Increasing leaching temperature from 45°C to 85°C did not improve recoveries of lanthanides. The most optimum condition was found at oxalic acid leaching of 1 mol/L, leaching temperature at 40°C, and time for 2 hours. The obtained results show that the lanthanides can be leached using oxalic axid. This finding may lead to more effective and economical method to separate lanthanides from low grade bauxite.

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Xiao, Hong-Ping, Jian Zhou, Rong-Qing Zhao, Wei-bing Zhang, and Yong Huang. "A series of lanthanoid selenidoantimonates(v): rare examples of lanthanoid selenidoantimonates based on dinuclear lanthanide complexes." Dalton Transactions 44, no. 13 (2015): 6032–39. http://dx.doi.org/10.1039/c5dt00146c.

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Zhou, Jian, Rong-Qing Zhao, Tao Yang, Xing Liu, Hong-Ping Xiao, Hua-Hong Zou, and Xiao-Feng Tan. "A series of new lanthanoid thioarsenates: insights into the influence of lanthanide contraction on the formation of new lanthanoid thioarsenates." Dalton Transactions 44, no. 16 (2015): 7203–12. http://dx.doi.org/10.1039/c4dt03912b.

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A series of new lanthanoid thioarsenates were prepared and they would be helpful for gaining insights into the influence of lanthanide contraction on the formation of other new lanthanoid thioarsenates.

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Vu, Huong N., Gabriel A. Subuyuj, Srividhya Vijayakumar, Nathan M. Good, N. Cecilia Martinez-Gomez, and Elizabeth Skovran. "Lanthanide-Dependent Regulation of Methanol Oxidation Systems in Methylobacterium extorquens AM1 and Their Contribution to Methanol Growth." Journal of Bacteriology 198, no. 8 (February 1, 2016): 1250–59. http://dx.doi.org/10.1128/jb.00937-15.

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ABSTRACTMethylobacterium extorquensAM1 has two distinct types of methanol dehydrogenase (MeDH) enzymes that catalyze the oxidation of methanol to formaldehyde. MxaFI-MeDH requires pyrroloquinoline quinone (PQQ) and Ca in its active site, while XoxF-MeDH requires PQQ and lanthanides, such as Ce and La. Using MeDH mutant strains to conduct growth analysis and MeDH activity assays, we demonstrate thatM. extorquensAM1 has at least one additional lanthanide-dependent methanol oxidation system contributing to methanol growth. Additionally, the abilities of different lanthanides to support growth were tested and strongly suggest that both XoxF and the unknown methanol oxidation system are able to use La, Ce, Pr, Nd, and, to some extent, Sm. Further, growth analysis using increasing La concentrations showed that maximum growth rate and yield were achieved at and above 1 μM La, while concentrations as low as 2.5 nM allowed growth at a reduced rate. Contrary to published data, we show that addition of exogenous lanthanides results in differential expression from thexox1andmxapromoters, upregulating genes in thexox1operon and repressing genes in themxaoperon. Using transcriptional reporter fusions, intermediate expression from both themxaandxox1promoters was detected when 50 to 100 nM La was added to the growth medium, suggesting that a condition may exist under whichM. extorquensAM1 is able to utilize both enzymes simultaneously. Together, these results suggest thatM. extorquensAM1 actively senses and responds to lanthanide availability, preferentially utilizing the lanthanide-dependent MeDHs when possible.IMPORTANCEThe biological role of lanthanides is a nascent field of study with tremendous potential to impact many areas in biology. Our studies demonstrate that there is at least one additional lanthanide-dependent methanol oxidation system, distinct from the MxaFI and XoxF MeDHs, that may aid in classifying additional environmental organisms as methylotrophs. Further, our data suggest thatM. extorquensAM1 has a mechanism to regulate which MeDH is transcribed, depending on the presence or absence of lanthanides. While the mechanism controlling differential regulation is not yet understood, further research into how methylotrophs obtain and use lanthanides will facilitate their cultivation in the laboratory and their use as a biomining and biorecycling strategy for recovery of these commercially valuable rare-earth elements.

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Barros, Joana M. F., Glauber J. T. Fernandes, Marcio D. S. Araujo, Dulce M. A. Melo, Amanda D. Gondim, Valter J. Fernandes, and Antonio S. Araujo. "Hydrothermal Synthesis and Properties of Nanostructured Silica Containing Lanthanide Type Ln–SiO2 (Ln = La, Ce, Pr, Nd, Eu, Gd, Dy, Yb, Lu)." Nanomaterials 13, no. 3 (January 18, 2023): 382. http://dx.doi.org/10.3390/nano13030382.

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The nanostructured lanthanide-silica materials of the Ln–SiO2 type (Ln = La, Ce, Pr, Nd, Eu, Gd, Dy, Yb, Lu) were synthesized by the hydrothermal method at 100 °C, using cetyltrimethylammonium as a structural template, silica gel and sodium silicate as a source of silicon, and lanthanide oxides, with Si/Ln molar ratio = 50. The resulting materials were calcined at 500 °C using nitrogen and air, and characterized by X-ray diffraction (XRD), Fourier-Transform infrared absorption spectroscopy, scanning electron microscopy, thermogravimetry (TG), surface area by the BET method and acidity measurements by n-butylamine adsorption. The XRD and chemical analysis indicated that the SiO2 presented a hexagonal structure and the incorporation of lanthanides in the structure changes the properties of the Ln–SiO2 materials. The heavier the lanthanide element, the higher the Si/Ln ratio. The TG curves showed that the decomposition of the structural template occurs in the materials at temperatures below 500 °C. The samples showed variations in specific surface area, mean pore diameter and silica wall thickness, depending on the nature of the lanthanide. The incorporation of different lanthanides in the silica generated acid sites of varied strength. The hydrothermal stability of the Ln–SiO2 materials evaluated at high temperatures, evidenced that the properties can be controlled for application in adsorption and catalysis processes.

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26

Liu, Juewen. "Lanthanide-dependent RNA-cleaving DNAzymes as metal biosensors." Canadian Journal of Chemistry 93, no. 3 (March 2015): 273–78. http://dx.doi.org/10.1139/cjc-2014-0465.

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Lanthanides represent a group of very important but challenging analytes for biosensor development. These 15 elements are very similar in their chemical properties. So far, limited success has been realized using the rational ligand design approach. My laboratory has successfully accomplished the task of carrying out combinatorial selection to isolate lanthanide-dependent RNA-cleaving DNAzymes. We report two new DNAzymes, each discovered in a different selection condition and both are highly specific to lanthanides. When both DNAzymes are used together, it is possible to identify the last few heavy lanthanides. Upon introducing a phosphorothioate modification, one of the abovementioned DNAzymes becomes highly active with many toxic heavy metals. With the selection of more DNAzymes with different activity patterns cross the lanthanide series, a sensor array might be produced for identifying each ion. This article is a minireview of the current developments on this topic and some of the historical aspects. It reflects the main content of the Fred Beamish Award presentation delivered at the 2014 Canadian Society for Chemistry Conference in Vancouver. Future directions in this area are also discussed.

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Dunaev, Anatoliy M., Vladimir B. Motalov, and Lev S. Kudin. "ELECTRON WORK FUNCTION OF LANTHANIDE TRIIODIDES." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 63, no. 11 (October 27, 2020): 13–20. http://dx.doi.org/10.6060/ivkkt.20206311.6292.

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Desorption enthalpies of LnI4– and Ln2I7– associative ions (Ln = La, Ce, Pr, Nd, Gd, Tb, Dy, Ho, Er, Tm, and Lu) and the enthalpy of sublimation of LnI3 molecules were determined by Knudsen effusion mass spectrometric technique. These data were used to calculate the effective values of electron work function φe of polycrystalline samples of lanthanide triiodides LnI3 for the first time. The calculation methodology is based on the study of thermochemical cycles, which include atoms, molecules, ions, and electrons being in thermodynamic equilibrium with the LnI3 crystal inside the effusion cell. The values obtained for different lanthanides turned out to be close. They lie in the range of about 2.4 – 4.4 eV with an average value in the series: φe = 3.2 ± 0.3 eV. The latter value is close to those for previously studied lanthanide tribromides. No secondary periodicity of φe was found within the calculated errors along the lanthanide series. The results obtained are in quantitative agreement with the theoretical calculation of the values of the band gap of lanthanide triiodides. Comparison of φe with other classes of lanthanide compounds such as oxides, hexaborides, and lanthanide metals shows relatively high electron emission ability yielding only to alkali and alkali-earth metals.

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28

Driscoll, Darren M., Frankie D. White, Subhamay Pramanik, Jeffrey D. Einkauf, Bruce Ravel, Dmytro Bykov, Santanu Roy, et al. "Observation of a promethium complex in solution." Nature 629, no. 8013 (May 22, 2024): 819–23. http://dx.doi.org/10.1038/s41586-024-07267-6.

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AbstractLanthanide rare-earth metals are ubiquitous in modern technologies1–5, but we know little about chemistry of the 61st element, promethium (Pm)6, a lanthanide that is highly radioactive and inaccessible. Despite its importance7,8, Pm has been conspicuously absent from the experimental studies of lanthanides, impeding our full comprehension of the so-called lanthanide contraction phenomenon: a fundamental aspect of the periodic table that is quoted in general chemistry textbooks. Here we demonstrate a stable chelation of the 147Pm radionuclide (half-life of 2.62 years) in aqueous solution by the newly synthesized organic diglycolamide ligand. The resulting homoleptic PmIII complex is studied using synchrotron X-ray absorption spectroscopy and quantum chemical calculations to establish the coordination structure and a bond distance of promethium. These fundamental insights allow a complete structural investigation of a full set of isostructural lanthanide complexes, ultimately capturing the lanthanide contraction in solution solely on the basis of experimental observations. Our results show accelerated shortening of bonds at the beginning of the lanthanide series, which can be correlated to the separation trends shown by diglycolamides9–11. The characterization of the radioactive PmIII complex in an aqueous environment deepens our understanding of intra-lanthanide behaviour12–15 and the chemistry and separation of the f-block elements16.

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29

Maza-Rodriguez, J., P. Olivera-Pastor, S. Bruque, and A. Jimenez-Lopez. "Exchange selectivity of lanthanide ions in montmorillonite." Clay Minerals 27, no. 1 (March 1992): 81–89. http://dx.doi.org/10.1180/claymin.1992.027.1.08.

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AbstractThe exchange of Ca2+ and Na+ by tanthanide ions (Ln3+ = Pr3+, Gd3+, Er3+) in montmorillonite was investigated at two different ionic strengths (0·01 and 0·1 mol/kg). Preferential sorption of Ln3+ was observed and variable selectivity coefficients were found depending upon the lanthanide concentration in the solid, and ionic strength. The highest exchange extent of Ln3+ always occurred for the system Na+/Ln3+, but the exchange selectivities of Ln3+ were generally higher in the exchange system Ca2+/Ln3+. Although the relative affinity of montmorillonite for the three lanthanide ions was similar, distinctive behaviour between Pr3+ and the heavier lanthanides, Gd3+ and Er3+, was noted. The study of Ln3+ adsorption in trace amounts showed specific adsorption of lanthanides at high concentrations of Na+ in the external solution and that the exchange stoichiometries in the interlayer regions were 3 : 1 at equilibrium pH = 4.

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30

Prosser, R. Scott, V. B. Volkov, and I. V. Shiyanovskaya. "Solid-state NMR studies of magnetically aligned phospholipid membranes: taming lanthanides for membrane protein studies." Biochemistry and Cell Biology 76, no. 2-3 (May 1, 1998): 443–51. http://dx.doi.org/10.1139/o98-058.

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The addition of lanthanides (Tm3+, Yb3+, Er3+, or Eu3+) to a solution of long-chain phospholipids such as dimyristoylphosphatidylcholine (DMPC) and short-chain phospholipids such as dihexanoylphosphatidylcholine (DHPC) is known to result in a bilayer phase in which the average bilayer normal aligns parallel to an applied magnetic field. Lanthanide-doped bilayers have enormous potential for the study of membrane proteins by solid-state NMR, low-angle diffraction, and a variety of optical spectroscopic techniques. However, the addition of lanthanides poses certain challenges to the NMR spectroscopist: coexistence of an isotropic phase and hysteresis effects, direct binding of the paramagnetic ion to the peptide or protein of interest, and severe paramagnetic shifts and line broadening. Lower water concentrations and larger DMPC/DHPC ratios than those typically used in bicelles consistently yield a single oriented bilayer phase that is stable over a wide range of temperature (~35-90°C). Among the above choice of lanthanides, Yb3+ is found to give minimal paramagnetic shifts and line broadening at acceptably low concentrations necessary for alignment (i.e., Yb3+/DMPC mole ratios equal to or greater than 0.01). Finally, the addition of a phospholipid chelate, 1,2-dimyristoyl-sn-glycero-3-phosphoethanolamine - diethylenetriaminepentaacetic acid, is observed to significantly reduce paramagnetic broadening and presumably prevent direct association of the peptide with the lanthanide ions.Key words: lanthanide, solid-state NMR, model membrane, membrane protein structure.

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31

Osamah Saud Salman and Tamer Khalil M Ali. "Investigate the scattering of electromagnetic waves from lanthanide nanoparticles by changing the size and shape of nanoparticles." Tikrit Journal of Pure Science 26, no. 6 (December 14, 2021): 66–72. http://dx.doi.org/10.25130/tjps.v26i6.194.

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The aim of this study was to evaluate the effect of change in particle size and shape of nano lanthanides and its effect on the distribution of electromagnetic waves. In this study, we investigated lanthanide nanoparticles for the scattering of electromagnetic waves in excitation factors such as the electronic properties of nanoparticles, the size and shape of nanoparticles, the temperature properties around nanoparticles and dielectric nanoparticles. In this study, lanthanide nanoparticles with CST software were used to simulate the scattering of electromagnetic waves. In this project, using the classical electromagnetic theory, the scattering of small dielectric particles in relation to this cross section of electromagnetic waves was investigated and the changes for different parameters were evaluated. Also, the rotation measured the cross-section of small particles by changing the parameters. Lanthanide nanoparticles in the 60 GHz to 120 GHz band were used to study the scattering of electromagnetic waves. The results showed that the yield of lanthanide particle nanometers was more than five nanometers in diameter and more than ten nanometers. We have shown that with the angular scattering of electromagnetic waves, lanthanide nanoparticles are more oval and more than a spherical shape.

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32

Zangana, Karzan H., Eufemio Moreno Pineda, and Richard E. P. Winpenny. "Tetrametallic lanthanide(iii) phosphonate cages: synthetic, structural and magnetic studies." Dalton Trans. 43, no. 45 (2014): 17101–7. http://dx.doi.org/10.1039/c4dt02630f.

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33

Hlava, P. F. "Problems in electron microprobe analysis of the lanthanides: The x-ray lines." Proceedings, annual meeting, Electron Microscopy Society of America 48, no. 2 (August 12, 1990): 200–201. http://dx.doi.org/10.1017/s0424820100134594.

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Electron microprobe analysis of materials that contain the lanthanide series of rare earth elements (REE) in natural abundance ratios presents a difficult and truly unique set of problems due to the their chemical and crystallographic similarity and the complexity of the L-spectra used for analysis. REEs differ from one another by the number of protons in their nuclei and the number of electrons in their second inner shell. There are two series of REEs - the lanthanides, from atomic number 58 through 71 and the actinides from 90 through 103. By convention, when most workers speak of the REEs they refer to the lanthanides plus lanthanum, often yttrium and rarely scandium (because these elements are geochemically associated with the lanthanides proper). The terms REE and lanthanide, when used in this paper, will refer to elements of atomic number 57 through 71. In all of these elements the two outer shells, where the valence electrons reside, are essentially identical resulting in chemical behavior that is also essentially identical.

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34

Shahbazi, Shayan, C. J. Oldham, Austin D. Mullen, John D. Auxier II, and Howard L. Hall. "Synthesis, thermogravimetric analysis and enthalpy determination of lanthanide β-diketonates." Radiochimica Acta 107, no. 12 (November 26, 2019): 1173–84. http://dx.doi.org/10.1515/ract-2018-3085.

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Abstract This work reports thermodynamic characterizations of lanthanide β-diketonates for use in nuclear fission product separation. Adsorption and sublimation enthalpies have been shown to be linearly correlated, therefore there is motivation to determine sublimation thermodynamics. An isothermal thermogravimetric analysis method is employed on fourteen lanthanide chelates for the ligands 2,2,6,6-tetramethyl-3,5-heptanedione and 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedione to determine sublimation enthalpies. No linear trend is seen across the series; values show a cyclical nature, possibly indicating a greater influence of chemisorption for some complexes and less of a role of physisorption in dictating adsorption differences between lanthanides in the same series. This is in line with previous reports in terms of the chromatographic separation order of the lanthanides. The results reported here can be used to manipulate separations parameters and column characteristics to better separate these lanthanide chelates. Fourteen chelates of the ligand 1,1,1-trifluoro-2,4-pentanedione are also thermally characterized but found to not sublime and be undesirable for this method. Additionally, all chelates are characterized by constant heating thermogravimetric analysis coupled with mass spectrometry, melting point analysis, elemental analysis and FTIR.

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35

Martín-Rodríguez, R., R. Valiente, F. Aguado, and A. C. Perdigón. "Highly efficient photoluminescence from isolated Eu3+ ions embedded in high-charge mica." J. Mater. Chem. C 5, no. 39 (2017): 10360–68. http://dx.doi.org/10.1039/c7tc01818e.

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Incorporation of lanthanide ions in synthetic clay minerals is a promising approach to combine the efficient sharp-line emission of lanthanides with the unique structural stability and high adsorption capacity of high-charge micas.

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36

Liu, Jingjing, Lydia E. Nodaraki, Philip J. Cobb, Marcus J. Giansiracusa, Fabrizio Ortu, Floriana Tuna, and David P. Mills. "Synthesis and characterisation of light lanthanide bis-phospholyl borohydride complexes." Dalton Transactions 49, no. 19 (2020): 6504–11. http://dx.doi.org/10.1039/d0dt01241f.

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Two families of lanthanide(iii) phospholyl borohydride complexes are reported (carbon = grey, hydrogen = white, oxygen = red, boron = yellow, phosphorus = magenta, potassium = blue, lanthanides = teal; only BH₄ hydrogens are shown for clarity).

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37

Gagné, Olivier Charles. "Bond-length distributions for ions bonded to oxygen: results for the lanthanides and actinides and discussion of the f-block contraction." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 74, no. 1 (January 12, 2018): 49–62. http://dx.doi.org/10.1107/s2052520617017425.

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Bond-length distributions have been examined for 84 configurations of the lanthanide ions and 22 configurations of the actinide ions bonded to oxygen, for 1317 coordination polyhedra and 10 700 bond distances for the lanthanide ions, and 671 coordination polyhedra and 4754 bond distances for the actinide ions. A linear correlation between mean bond length and coordination number is observed for the trivalent lanthanides ions bonded to O2−. The lanthanide contraction for the trivalent lanthanide ions bonded to O2− is shown to vary as a function of coordination number, and to diminish in scale with an increasing coordination number. The decrease in mean bond length from La3+ to Lu3+ is 0.25 Å for coordination number (CN) 6 (9.8%), 0.22 Å for CN 7 (8.7%), 0.21 Å for CN 8 (8.0%), 0.21 Å for CN 9 (8.2%) and 0.18 Å for CN 10 (6.9%). The crystal chemistry of Np5+ and Np6+ is shown to be very similar to that of U6+ when bonded to O2−, but differs for Np7+.

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38

Chu, Frances, David A. C. Beck, and Mary E. Lidstrom. "MxaY regulates the lanthanide-mediated methanol dehydrogenase switch inMethylomicrobium buryatense." PeerJ 4 (September 7, 2016): e2435. http://dx.doi.org/10.7717/peerj.2435.

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Many methylotrophs, microorganisms that consume carbon compounds lacking carbon–carbon bonds, use two different systems to oxidize methanol for energy production and biomass accumulation. The MxaFI methanol dehydrogenase (MDH) contains calcium in its active site, while the XoxF enzyme contains a lanthanide in its active site. The genes encoding the MDH enzymes are differentially regulated by the presence of lanthanides. In this study, we found that the histidine kinase MxaY controls the lanthanide-mediated switch inMethylomicrobium buryatense5GB1C. MxaY controls the transcription of genes encoding MxaFI and XoxF at least partially by controlling the transcript levels of the orphan response regulator MxaB. We identify a constitutively active version of MxaY, and identify the mutated residue that may be involved in lanthanide sensing. Lastly, we find evidence to suggest that tight control of active MDH production is required for wild-type growth rates.

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39

González Chávez, Fernando, and Hiram Isaac Beltrán. "Tuning dimensionality between 2D and 1D MOFs by lanthanide contraction and ligand-to-metal ratio." New Journal of Chemistry 45, no. 15 (2021): 6600–6610. http://dx.doi.org/10.1039/d0nj04055j.

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2D/1D dimensionality tuning in LnMOFs is related to both (i) ligand-to-metal ratio and (ii) lanthanide contraction, this is only possible with Er/Tm, lighter lanthanides e.g. Pr only produced 2D MOFs, despite different ligand-to-metal ratios were used.

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40

Nikolova, Valya, Nikoleta Kircheva, Stefan Dobrev, Silvia Angelova, and Todor Dudev. "Lanthanides as Calcium Mimetic Species in Calcium-Signaling/Buffering Proteins: The Effect of Lanthanide Type on the Ca2+/Ln3+ Competition." International Journal of Molecular Sciences 24, no. 7 (March 27, 2023): 6297. http://dx.doi.org/10.3390/ijms24076297.

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Lanthanides, the 14 4f-block elements plus Lanthanum, have been extensively used to study the structure and biochemical properties of metalloproteins. The characteristics of lanthanides within the lanthanide series are similar, but not identical. The present research offers a systematic investigation of the ability of the entire Ln3+ series to substitute for Ca2+ in biological systems. A well-calibrated DFT/PCM protocol is employed in studying the factors that control the metal selectivity in biological systems by modeling typical calcium signaling/buffering binding sites and elucidating the thermodynamic outcome of the competition between the “alien” La3+/Ln3+ and “native” Ca2+, and La3+ − Ln3+ within the lanthanide series. The calculations performed reveal that the major determinant of the Ca2+/Ln3+ selectivity in calcium proteins is the net charge of the calcium binding pocket; the more negative the charge, the higher the competitiveness of the trivalent Ln3+ with respect to its Ca2+ contender. Solvent exposure of the binding site also influences the process; buried active centers with net charge of −4 or −3 are characterized by higher Ln3+ over Ca2+ selectivity, whereas it is the opposite for sites with overall charge of −1. Within the series, the competition between La3+ and its fellow lanthanides is determined by the balance between two competing effects: electronic (favoring heavier lanthanides) and solvation (generally favoring the lighter lanthanides).

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Gallardo, Piedraescrita, Elisa Abas, Alicia Buceta, Francisco Merchán, Asunción Luquin, Saif A. Haque, and Mariano Laguna. "A Series of [Ln(NO₃)₃(4’-(4-Bromophenyl)-2,2’:6’,2’’-Terpyridine)] Lanthanide Derivatives." Solid State Phenomena 257 (October 2016): 160–64. http://dx.doi.org/10.4028/www.scientific.net/ssp.257.160.

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Lanthanide complexes [Ln (NO3)3(4’-(4-bromophenyl)-2,2’:6’,2’’-terpyridine)]; being Ln all the non radiative lanthanide elements (1 – 14), have been synthesized and characterized by IR, 1H NMR, MALDI-MS and the X-ray structures of the La, Nd, Sm, Eu and Dy complexes, showing a linear comparison of the average M-O and M-N distances with the ionic radius or the number of f electrons of the lanthanides. The luminescence properties of complexes 4 (Nd), 5 (Sm), 6 (Eu), 8 (Tb), 9 (Dy) in the solid state and in the acetonitrile solutions of 5 (Sm) and 6 (Eu) are reported.

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Li, Yuyang, and Ronald Kluger. "Increased efficiency in biomimetic Lewis acid–base pair catalyzed monoacylation of diols by acyl phosphate monoesters." FACETS 2, no. 2 (September 1, 2017): 682–89. http://dx.doi.org/10.1139/facets-2017-0047.

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Acyl phosphate monoesters are biomimetic acylation reagents that require coordination to metal ions to react with cis-diol substrates in water. With lanthanide catalysts, outcomes are compromised by (1) the competitive lanthanide-promoted hydrolysis of the acyl phosphate reagents as well as by (2) the high affinity of lanthanum ions for the phosphate monoester by-product. Based on analysis of the mechanism of the process, optimizing reaction conditions can selectively inhibit the lanthanum-promoted hydrolysis of acyl phosphate monoesters. Furthermore, using zinc salts and lead salts in place of lanthanides enhances the reactivity of the reactants and causes less complexation of the metal ion with the by-products.

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Alakhras, Fadi. "Kinetic Studies on the Removal of Some Lanthanide Ions from Aqueous Solutions Using Amidoxime-Hydroxamic Acid Polymer." Journal of Analytical Methods in Chemistry 2018 (July 8, 2018): 1–7. http://dx.doi.org/10.1155/2018/4058503.

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Lanthanide metal ions make distinctive and essential contributions to recent global proficiency. Extraction and reuse of these ions is of immense significance especially when the supply is restricted. In light of sorption technology, poly(amidoxime-hydroxamic) acid sorbents are synthesized and utilized for the removal of various lanthanide ions (La3+, Nd3+, Sm3+, Gd3+, and Tb3+) from aqueous solutions. The sorption speed of trivalent lanthanides (Ln3+) depending on the contact period is studied by a batch equilibrium method. The results reveal fast rates of metal ion uptake with highest percentage being achieved after 15–30 min. The interaction of poly(amidoxime-hydroxamic) acid sorbent with Ln3+ ions follows the pseudo-second-order kinetic model with a correlation coefficient R2 extremely high and close to unity. Intraparticle diffusion data provide three linear plots indicating that the sorption process is affected by two or more steps, and the intraparticle diffusion rate constants are raised among reduction of ionic radius of the studied lanthanides.

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de Melo, Fernando, Sabrina Almeida, and Henrique Toma. "Magnetic Nanohydrometallurgy Applied to Lanthanide Separation." Minerals 10, no. 6 (June 11, 2020): 530. http://dx.doi.org/10.3390/min10060530.

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Lanthanides play an important role in modern technology because of their outstanding optical, electronic, and magnetic properties. Their current hydrometallurgical processing involves lixiviation, leading to concentrates of elements whose separation requires exhaustive procedures because of their similar chemical properties. In this sense, a new nanotechnological approach is here discussed, involving the use of iron oxide nanoparticles functionalized with complexing agents, such as diethylenetriaminepentaacetic acid (DTPA), for carrying out the magnetic extraction and separation of the lanthanide ions in aqueous solution. This strategy, also known as magnetic nanohydrometallurgy (MNHM), was first introduced in 2011 for dealing with transition metal recovery in the laboratory, and has been recently extended to the lanthanide series. This technology is based on lanthanide complexation and depends on the chemical equilibrium involved. It has been better described in terms of Langmuir isotherms, considering a uniform distribution of the metal ions over the nanoparticles surface, as evidenced by high angle annular dark field microscopy. The observed affinity parameters correlate with the lanthanide ion contraction series, and the process dynamics have been studied by monitoring the nanoparticles migration under an applied magnetic field (magnetophoresis). The elements can be reversibly captured and released from the magnetically confined nanoparticles, allowing their separation by a simple acid-base treatment. It can operate in a circular scheme, facilitated by the easy magnetic recovery of the extracting agents, without using organic solvents and ionic exchange columns. MNHM has been successfully tested for the separation of the lanthanide elements from monazite mineral, and seems a promising green nanotechnology, particularly suitable for urban mining.

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45

Gao, Qi, Shuai Han, Qing Ye, Shuiyuan Cheng, Tianfang Kang, and Hongxing Dai. "Effects of Lanthanide Doping on the Catalytic Activity and Hydrothermal Stability of Cu-SAPO-18 for the Catalytic Removal of NOx (NH3-SCR) from Diesel Engines." Catalysts 10, no. 3 (March 17, 2020): 336. http://dx.doi.org/10.3390/catal10030336.

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Lanthanide (La, Ce, Nd, Gd, Tb, Ho or Lu)-doped Cu-SAPO-18 samples were prepared using the ion-exchange method. Physicochemical properties of the samples were systematically characterized by a number of analytical techniques, and the effects of lanthanide doping on catalytic activity and hydrothermal stability of the Cu-SAPO-18 catalysts for the NH3-SCR reaction were examined. It is shown that the doping of lanthanide elements could affect the interaction between the active components (copper ions) and the AEI-structured SAPO-18 support. The inclusion of some lanthanides significantly slowed down hydrolysis of the catalyst during hydrothermal aging treatment process, leading to an enhanced catalytic activity at both low and high temperatures and hydrothermal stability. In particular, Ce doping promoted the Cu2+ ions to migrate to the energetically favorable sites for enhancement in catalytic activity, whereas the other lanthanide ions exerted little or an opposite effect on the migration of Cu2+ ions. Additionally, Ce doping could improve hydrothermal stability of the Cu-SAPO-18 catalyst by weakening hydrolysis of the catalyst during the hydrothermal aging treatment process. Ce doping increased the catalytic activity of Cu-SAPO-18 at low and high temperatures, which was attributed to modifications of the redox and/or isolated Cu2+ active centers.

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46

Semenishyn, Nikolay, Serhii Smola, Mariia Rusakova, and Natalia Rusakova. "4f-LUMINESCENCE OF LANTHANIDE IONS IN REGIOISOMERIC CORROLE COMPLEXES." Ukrainian Chemistry Journal 87, no. 9 (October 25, 2021): 35–44. http://dx.doi.org/10.33609/2708-129x.87.09.2021.35-44.

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Isomeric ditopic corroles and complexes of Yb (III), Nd (III) and Er (III) based on them were synthesized and corrole-photosensitized 4f-luminescence in near infrared region was revealed. The structure of isomeric complexes allows adjusting the distance between the corrole core and lanthanide ion. The obtained results show that the sensitization mechanism changes drastically for both different lanthanides and isomeric forms.

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47

Romanova, Kseniya A., and Yuriy G. Galyametdinov. "Simulation of Energy Transfer Processes in Mesogenic Binuclear Complexes of Lanthanides(III)." Liquid Crystals and their Application 24, no. 1 (March 28, 2024): 22–35. http://dx.doi.org/10.18083/lcappl.2024.1.22.

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Quantum-chemical simulation of the molecular structure and excited state energies of some mesogenic binuclear complexes of lanthanides(III) with substituted β-diketones and Lewis bases have been performed. Correlations between geometric parameters, structural features of the complexes' coordination polyhedra, potential liquid-crystalline properties, and luminescence efficiency were analyzed. According to the calculated values of the lowest singlet and triplet excited states of the ligands, energy level diagrams were constructed and the main channels of intramolecular energy transfer between the excited levels of the ligands and lanthanide(III) ions were defined. The process of interionic energy transfer was elucidated and the ligand environment for the creation of mesogenic binuclear lanthanide(III) complexes with intense luminescence was proposed.

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Vassiliev, Valery P., Valery A. Lysenko, and Marcelle Gaune-Escard. "Relationship of thermodynamic data with Periodic Law." Pure and Applied Chemistry 91, no. 6 (June 26, 2019): 879–93. http://dx.doi.org/10.1515/pac-2018-0717.

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Abstract Relationships between the various physical and chemical properties of isostructural compounds take place according to the Periodic Table that is a fundamental basis of Chemistry. The systematization of this approach, data vs. the Periodic Table, will contribute to further development of the solid state chemistry theory. The lanthanides and the actinides make up the f block of the Periodic Table. The lanthanides are the elements produced as the 4f sublevel is filled with electrons and the actinides are formed while filling the 5f sublevel. In this paper, we analyze some classes of compounds formed by the lanthanides with other elements of the Periodic Table, which can count into the thousands of binary compounds. The special place of lanthanides in the Periodic System of Elements made it possible to establish strict nonlinear relationships between the standard entropy and the lanthanide atomic number of the compounds Ln2X3 (X = O, S, Se, Te), LnN, LnB4, and LnF3 in the solid state. This relationship, based on tetrad-effect, can be applied to other physical and chemical properties of the isostructural compounds. The thermodynamic properties of actinides have been studied much less than lanthanides, but the similarity of physicochemical properties makes it possible for us to estimate, with sufficient accuracy, unexplored properties using fundamental laws. One of these laws is the tetrad-effect concept that is an effective tool to predict missing thermodynamic values for lanthanide and actinide compounds and to rationally plan experiments.

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Vorob’ev, Vladimir Nikolaevich, Sergei Fedorovich Kotov, Vera Vladimirovna Nikolenko, Denis Vladimirovich Tishin, and Alexander Loenidovich Mikhailov. "INFLUENCE OF LIGHT AND HEAVY LANTHANIDES ON THE PHYSIOLOGICAL PROCESSES OF Taraxacum hybernum." Journal of Experimental Biology and Agricultural Sciences 8, Spl-2-AABAS (December 15, 2020): S298—S302. http://dx.doi.org/10.18006/2020.8(spl-2-aabas).s298.s302.

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The current study was carried out to study the influence of light and heavy lanthanides on the physiological process of Crimean-Sagyz/ Krim-saghyz (dandelion - Taraxacum hybernum). Lanthanide belongs to the group of light or heavy; infiltration of dandelion (Crimean saghyz) seeds with light and heavy lanthanides solutions increased the germination energy by 26%. The differences in the influence of light (cerium) and heavy (lutetium) were manifested in the quantum efficiency change of the photosystem 2 (PS II). Treatment of leaves with high concentrations (100 µM) led to a decrease of Y (II), moreover, under the influence of light lanthanide, the decrease was greater by 21%. It is assumed that the effect of the used lanthanides on the dandelion photosynthetic apparatus is multidirectional. Cerium influenced the PS II antenna complex, and lutetium influenced the reaction centers. A 10-fold decrease in the concentration did not change the nature of cerium action, except that Y (II) was restored already on the second day after treatment. The effect of lutetium became noticeable only by the 8th day after treatment when Y (II) became higher than that of untreated plants. Thus, the results of the study suggested that in dandelion leaves, lanthanides with a concentration of 10 µM increased the quantum efficiency of PS II in contrast to cerium.

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Rukk, N. S., R. M. Zakalyukin, and A. Yu Skryabina. "LANTHANIDE OXYIODIDES." Fine Chemical Technologies 11, no. 1 (February 28, 2016): 5–22. http://dx.doi.org/10.32362/2410-6593-2016-11-1-5-22.

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The present review is devoted to consideration and generalization of a number of synthetic methods for lanthanide oxoiodides preparation as well as to consideration of their structural particularities and thermal stability. Phase diagrams with the participation of REE oxoiodides, alkaline metal iodides or silver iodide are given and discussed. All the systems are characterized by the solid solution formation on the basis of the pure compounds, while the systems with the participation of alkaline metal iodides are characterized by the formation of incongruent melting compounds. Structural data concerning oxoiodides of lanthanides with different oxidation states and with the participation of some other elements (carbon, nitrogen, barium, osmium, etc) are present and overviewed. Possible areas of application (catalysis, X-ray detectors, medical diagnostics) including distinct luminescent properties of Ce-, Pr-, Nd-, Sm-doped REE oxoiodides are underlined.

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Journal articles on the topic 'Lanthanide'

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