Isomorphic substitution of neodymium and gadolinium for calcium in synthetic hydroxovanadate |
| |
Authors: | E I Get’man T A Shul’gina S N Loboda L Carrison |
| |
Institution: | (1) Donetsk National University, Donetsk, Ukraine;(2) East-Ukrainian National University, Lugansk, Ukraine;(3) Minnesota State University, Mankato, USA |
| |
Abstract: | Isomorphic substitution of neodymium and gadolinium for calcium in synthetic hydroxovanadate Ca5 ? x M x (VO4)3(OH)1 ? x O x (M = Nd, Gd) is studied in the range 700–1000°C using X-ray powder diffraction, single-crystal X-ray diffraction (Rietveld technique), and IR spectroscopy. Single-phase solid solutions at 800°C are formed with x ≤ 0.35 for M(III) = Nd and x ≤ 0.3 for M(III) = Gd. With high x, the apatite solid solution coexists with Ca3(VO4)2, Nd2O3, and X phases. With increasing x in the homogeneous region, the intensity of the bands of stretching vibrations and librations of OH groups decrease. Single-crystal X-ray diffraction shows that neodymium and gadolinium substitute for calcium in solid solutions mostly in Ca(2) positions. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|