A DIRECT N-15 NMR-STUDY OF ERBIUM(III)-NITRATE COMPLEXATION IN AQUEOUS SOLVENT MIXTURES

被引:18
作者
FRATIELLO, A
KUBOANDERSON, V
AZIMI, S
MARINEZ, E
MATEJKA, D
PERRIGAN, R
YAO, B
机构
[1] Department of Chemistry and Biochemistry, California State University, Los Angeles, Los Angeles, 90032, CA
关键词
H-1; N-15; CHLORINE-35; NMR; ERBIUM NITRATE; COMPLEXATION; ACETONE; METHANOL;
D O I
10.1007/BF01074951
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
The extent of inner-shell ion-pair formation of Er3+ with nitrate ion in aqueous mixtures has been studied by nitrogen-15 (N-15) NMR spectroscopy. At low temperature, exchange is slow enough to permit the direct observation of N-15 signals for nitrate ions in the Er3+ solvation shell and in bulk medium. In water-acetone mixtures, N-15 NMR signals for the mono- and bis complexes are observed at low nitrate to Er3+ mole ratios, but only the bis complex is evident at higher anion concentrations. No spectral evidence for the tris complex was seen at any nitrate concentration. In water-methanol-acetone mixtures, signals for the mono and bis complexes persist even at higher nitrate concentrations, indicating a reduced tendency to ion-pair with increasing dielectric constant. Preliminary N-15 NMR results are presented for the nitrate complexes of other paramagnetic lanthanide ions.
引用
收藏
页码:893 / 903
页数:11
相关论文
共 26 条