Structures and phase transitions of trigonal ZrMo2O8 and HfMo2O8.
This paper describes the structures, thermal-expansion properties and phase transitions of the trigonal forms of ZrMo(2)O(8) and HfMo(2)O(8). Both phases adopt a P(-)3m structure at room temperature and show positive thermal expansion. Both phases also undergo a displacive phase transition at high temperature (ZrMo(2)O(8) at 487 K and HfMo(2)O(8) at 463 K) to a higher-symmetry structure that has lower thermal expansion. The structure of the high-temperature alpha'-AMo(2)O(8) form (A = Zr and Hf) has been refined from powder diffraction data in space group P(-)3m1.
Allen
Simon
S
Department of Chemistry, University of Durham, Science Laboratories, South Road, Durham DH1 3LE, UK.
Ward
Rebecca J
RJ
Hampson
Matthew R
MR
Gover
Richard K B
RK
Evans
John S O
JS