The lanthanide contraction is a widely known phenomenon in which the ionic radii of the Ln ions decrease across the series from La to Lu. As a result, the distance (Ln-Y), where Y is a ligand donor atom, decreases across the series. As shown previously, the decrease normally has a linear dependence on the number of 4f Ln electrons, , and the net change, Δ', is between 0.15 and 0.20 Å. However, previous reports have shown that Δ' can be much larger than normal, and it is shown here that Δ' can be much smaller than normal. The present study seeks to determine the source and a possible explanation of these anomalies. A definitive conclusion is that the large Δ' is due to large (Ln-Y) for the early lanthanides. The small Δ' can result from chelate constraints and intramolecular H-bonding. As an outgrowth of this search, it is shown that consistent radii for donor atoms, (Y), can be obtained if the system satisfies certain conditions. Finally, the impact of the results on the normal and inverse trans influences is discussed.
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http://dx.doi.org/10.1021/acs.inorgchem.4c03698 | DOI Listing |
Inorg Chem
January 2025
Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
The lanthanide contraction is a widely known phenomenon in which the ionic radii of the Ln ions decrease across the series from La to Lu. As a result, the distance (Ln-Y), where Y is a ligand donor atom, decreases across the series. As shown previously, the decrease normally has a linear dependence on the number of 4f Ln electrons, , and the net change, Δ', is between 0.
View Article and Find Full Text PDFInorg Chem
January 2025
School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, United States.
While several ligand systems support uranium across a range of oxidation states, spanning more than two oxidation states in a conserved coordination geometry is uncommon among structurally authenticated complexes. Imidophosphorane ligands significantly stabilize high-valent lanthanide and actinide complexes. Here, we report a series of homoleptic uranium imidophosphorane complexes, spanning the +4, +5 and +6 oxidation states in a four-coordinate pseudotetrahedral ligand field.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
January 2025
Laboratory for Spectroscopy, Molecular Modeling and Structure Determination, Institute of Nuclear Chemistry and Technology, 16 Dorodna Street, 03-195 Warsaw, Poland. Electronic address:
The Raman spectra of lanthanide [Ln(HO)(Ala)](ClO) crystals were measured with 488, 532, 633, and 1064 nm laser lines, and ROA of complexes in water were collected using 532 nm excitation. As in IR and VCD, ν(CO) stretching and β(OCO) bending vibration bands showed a tendency typical to the lanthanide contraction effect. However, in Raman, the effect is less pronounced than the IR spectrum because it is strongly perturbed by lanthanide ion luminescence, which comes from the 4f → 4f transitions.
View Article and Find Full Text PDFClin Transl Sci
January 2025
University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
Despite the widespread use of currently available serum phosphate management options, elevated serum phosphate is common in patients with end-stage kidney disease on dialysis. Characteristics of currently available phosphate binders that lead to poor patient experiences such as large drug volume size of required daily medication (e.g.
View Article and Find Full Text PDFChem Asian J
December 2024
Solid State and Materials Chemistry Laboratory, Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, India, 110016.
The crystallization of lanthanide-containing β-octamolybdate (β-{MoO}) based solids from a binary 1 : 1 (water/DMSO) solution under ambient conditions is reported. A uniform synthetic protocol yielded three structurally related series of general composition {Ln(solvent)}[NaMoO] ⋅ yHO, with the whole lanthanide series (except for radioactive Pm). The three series are (i) {Ln(DMSO)}[NaMoO] ⋅ 0.
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