Página 20 dos resultados de 7330 itens digitais encontrados em 0.011 segundos
Resultados filtrados por Publicador: American Chemical Society

1H NMR in Solution and Solid State Structural Study of Lanthanide(III) Cryptates

Platas, C.; Avecilla, F.; Blas, A. de; Geraldes, C. F. G. C.; Rodríguez-Blas, T.; Adams, H.; Mahía, J.
Fonte: American Chemical Society Publicador: American Chemical Society
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
368.0147%
We present here a detailed structural comparison, both in the solid state and in aqueous solution, of a complete series of lanthanide cryptate complexes of a Schiff base axial macrobicyclic ligand L of general formula [LnL][NO3]3·xH2O (Ln = La−Lu, Y); the macrobicyclic receptor L is an azacryptand N[(CH2)2NCH−R−CHN(CH2)2]3N (R = m-C6H2OH-2-Me-5). The crystal structures of the Ce, Nd, and Eu complexes, chemical formulae [CeL(NO3)](NO3)2·1.5H2O·0.5CH3CH2OH (3), [NdL(NO3)](NO3)2·3H2O (5), and [EuL(NO3)](NO3)2·H2O· CH3OH (7), as well as that of [YL(NO3)][Y(NO3)3(H2O)2EtOH](NO3)2.EtOH·CH3CN (16), have been determined by single-crystal X-ray crystallography. The four crystals crystallize in the triclinic space group P with Z = 2; a = 10.853(3) Å, b = 12.746(3) Å, c = 17.907(5) Å, α = 98.09(2)°, β = 89.99(2)°, γ = 96.34(2)°, for 3; a = 10.835(2) Å, b = 12.544(3) Å, c = 17.701(2) Å, α = 82.220(10)°, β = 89.240(10)°, γ = 84.45(2)° for 5; a = 10.896(2) Å, b = 12.566(4) Å, c = 17.688(3) Å, α = 81.23(2)°, β = 89.500(10)°, γ = 84.72(3)° for 7; and a = 12.723(2) Å, b = 14.047(3) Å, c = 16.943(2) Å, α = 66.07(2)°, β = 79.838(12)°, γ = 81.616(14)° for 16. In light of their crystal structures, it can be stated that all of them adopt very similar structures...