An X-ray and NMR Study on Cerium(III) and Magnesium(II) Perchlorate Solutions

Abstract

A n X -ra y a n d N M R S tu d y o n C e r iu m ( I I I ) a n d M a g n e s iu m ( I I) P e r c h lo r a te S o lu tio n s R. Caminiti3, G. Cerioni6, G. Crisponi3, and P. Cuccaa a Istituto di Chimica Generale, Inorganica e Analitica, Via Ospedale 72, 09100 Cagliari (Italy). b Istituto di Chimica Farmaceutica e Tossicologica, Via Ospedale 72, 09100 Cagliari (Italy).Z. Naturforsch. 43 a, 317-325 (1988); received October 15, 1987 Metal-perchlorate solutions have been investigated by the X-ray scattering technique and 35C1 NMR spectroscopy. The aim of this work was to obtain structural information on the complex formation between the Cerium and the Perchlorate group and on the C104 -H20 interactions. The NMR data, the correlation functions and the analysis of the structure functions agree with the literature information about the Ce -(0C103). species present in aqueous solutions. Good agree ment with experimental data is achieved through a model in which the Perchlorate ions are bonded as monodentate ligands to the Cerium(III). No complex formation is confirmed for Mg(II). The cations also possess a second coordination shell of water molecules. Some indications have been obtained supporting the presence of C104 -H20 contacts.

The structure of concentrated aqueous solutions of chromium nitrate and cerium chloride studied by X-ray diffraction and Raman spectroscopy

“…In this contribution results obtained for chromium nitrate and cerium chloride solutions are discussed. Aqueous solutions of the salts here mentioned have been discussed by several authors [26,27,[56][57][58][59][60][61][62][63][64][65][66][67][68][69][70].…”

The Arrangement of First- and Second-Sphere Water Molecules in Divalent Magnesium Complexes: Results from Molecular Orbital and Density Functional Theory and from Structural Crystallography

“…The number of water molecules that complete the second hydration sphere of Mg 2+ has been estimated in a variety of studies to be approximately 12, ,,,, but this number is much less certain. For example, in a recent molecular dynamics simulation Martinez et al found a second shell hydration number for Mg 2+ of 13.…”

Ion solvation and association and water structure in an aqueous cerium (III) chloride solution in the gigapascal pressure range

“…The ambient value is consistent with the nine-fold coordination previously confirmed by other methods. [11][12][13][14][15][16][17][18][19][20] In the literature, nine water molecules are arranged in a tricapped trigonal prism configuration around Ce 3+ (Fig. 3).…”

“…In the present study, we focus on the solvation of Ce 3+ as the light rare earth ions since an aqueous CeCl3 solution is an attractive catalyst for biomass 9 and Ce 3+ exerts diverse biological effects in vivo substitution in biomolecule, mainly by their resemblance to Ca 2+ ions. 10 The solvation of Ce 3+ in an ambient condition has been widely investigated by large-angle X-ray diffraction, 11 EXAFS, 12,13 Raman spectroscopy, 14 EXAFS combined with MD simulation, 15,16 Hartee-Fock MO, 17 INDO/S-CI MO, 18 and QM/MM-MD approach. 19,20 From these studies, it has been established that Ce 3+ has nine-fold coordination in tri-capped trigonal prism with the Ce 3+ -H2O distance of 2.52~2.59 Å.…”

“…This structural change is observed in the corresponding radial distribution functions. At 0 GPa/300 K, the first peak is observed at 2.72 Å which should be ascribed to the sum of the contributions of both the Ce 3+ -H2O bonds (2.52~2.57 Å [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] ) due to the cation hydration and the 1 st neighbor H2O-H2O bonds (2.79~2.82 Å 6,7 ). The Cl-H2O bonds (3.16~3.18 Å 6,7 ) also contribute in part to the 2.72 Å peak.…”