An Anomalous X-ray Diffraction Study of Yttrium(III) Hydration

• Published in: The journal of physical chemistry. B 2001-04, Vol.105 (14), p.2694-2698
• Main Authors: Ramos, S, Neilson, G. W, Barnes, A. C, Mazuelas, A
• Format: Article
• Language: English
• ISSN: 1520-6106; 1520-5207
• DOI: 10.1021/jp003869c

Anomalous X-ray Diffraction (AXD) methods were used to determine the hydration structure of Y3+ in a 3.5 m solution of yttrium chloride in water. Data were gathered at two wavelengths below the absorption edge of Y3+. The data were corrected for attenuation, inelastic scattering and background and container scattering. They were then renormalized and put on an absolute scale of electron units. Fourier transformation of the results provided information on the Y3+ hydration. It is found that the short range order around Y3+ is well established with two well-defined hydration shells. The first, with Y3+···H2O centered at around 2.30 Å contains 8 water molecules, and the second with Y3+···O and Y3+···Cl- is centered at 4.77 Å. The results are in excellent agreement with a recent EXAFS+XANES study. Moreover, it can be shown that the contributions to the first hydration shell from O and H can be resolved in to two peaks, with maxima at 2.28 and 2.95 Å respectively. However, it is not possible to accurately determine coordination numbers for these Y3+···O and Y3+···H correlations independently due to the approximate nature of the calculations.