Crystal structures of hydrated lanthanide(III) nicotinates, La2(C5H4NCO2)6(H2O)4 and Sm2(C5H4NCO2)6(H2O)4

Abstract

The crystal structures of the hydrated nicotinate complexes of lanthanum(III) and samarium(III) have been determined by three-dimensional X-ray diffraction techniques using Patterson and Fourier syntheses. The compounds have the empirical formula [Ln(C SH 4NC02) 3(H20)2] and crystallize in space group Fife with lattice parameters a = 9.805 (5) A,b= 12.

Cerium 3,5-Dinitrobenzoate Dihydrate

“…Within the polymeric chains, only the bridging type of bonding exists. Ce--O distances vary between 2.400(5) and 2.661 (5),~, resulting in a strongly distorted square-antiprism arrangement around Ce. Comment Structural studies of rare earth carboxylates have shown that the carboxylate groups may be coordinated simultaneously in three modes, namely, chelating, bridging and chelating-bridging (Ma, Jin & Ni, 1994a,b;Hiyalov, Amiraslanov, Mamedov & Mrvsiimov, 1981;Bats, Klaus & Fuess, 1979;Moore, Glick & Baker, 1971). In the present study, we describe the structure of the title compound, (I), which shows only the bridging type of bonding within the polymeric chain.…”

The Polymeric Structure of Aquacadmium Bisnicotinate

“…A number of hydrated metal nicotinate structures have been reported. In the case of lanthanide complexes (with La, Pr, Sm, Ho or Tm) these are dinuclear, with both chelating and bridging nicotinate ligands (Moore, Glick & Baker, 1972;Aslanov, Abdul'minev & Porai-Koshits, 1972;Prout, Matin & Hutchinson, 1985), except for a polymeric lanthanum complex containing only bridging nicotinates (Kay, Moore & Glick, 1972); the N atom of the ligand is not involved in binding to the metals. Complexes of Cr, Co and Zn are mononuclear, and involve binding only to the N atom, with no coordination by the carboxylate group (Cotton, Falvello, Ohlhausen, Murillo & Quesada, 1991;Anagnostopoulos, Drew & Walton, 1969).…”

Rare-earth nicotinates: structures of tetra-μ-nicotinato-O,O'-bis[diaqua(nicotinato-O,O')holmium(III)], [Ho(C5H4NCO2)3(H2O)2]2, and tetra-μ-nicotinato-O,O'-bis[diaqua(nicotinato-O,O')thulium(III)], [Tm(C5H4NCO2)3(H2O)2]2

“…X-ray crystallographic studies by Moore, Glick & Baker (1972) have shown that the monoclinic crystals of the dimeric lanthanoid nicotinates, [Ln(C5H4NCOz)3(H20)212, have a structure with spacegroup symmetry P21/c. In addition to the La complex, the structures of the species containing the ions Sm 3+ (Moore et al, 1972), Nd a+ Gd 3+ and Er 3+ (Glick, private communication) have been determined. In these structures the rare-earth ions occur in relatively isolated pairs, thus affording an opportunity for studies, by magnetic resonance and optical spectroscopy, of the pair-wise interactions between rare-earth ions that are relatively free of the complicating presence of the single-ion and triple-ion systems that occur when paramagnetic ions are dilutely substituted at La sites in ionic crystals.…”