NI2+ COORDINATION IN AQUEOUS NICL2 SOLUTIONS - STUDY OF THE EXTENDED X-RAY ABSORPTION FINE-STRUCTURE

Extended x-ray absorption fine structure measurements are reported for aqueous NiCl2 solutions of molar concentration 2.78 and 3.74. Analysis of the Fourier filtered spectra by a multiparameter fitting procedure reveals a first coordination sphere consisting of six water molecules with an Ni-O bond distance of 2.07 Å, and no first sphere Ni-Cl coordination. Measurement of an outer coordination sphere consisting of both Cl- ions and water molecules is also reported. The relationship of these results to previously postulated ordered structures in these solutions is discussed. © 1979 American Institute of Physics.