Neutron and X-Ray Structure Refinements between 15 and 1073 K of Piezoelectric Gallium Arsenate, GaAsO4: Temperature and Pressure Behavior Compared with Other α-Quartz Materials
✍ Scribed by E. Philippot; P. Armand; P. Yot; O. Cambon; A. Goiffon; G.J. McIntyre; P. Bordet
- Publisher
- Elsevier Science
- Year
- 1999
- Tongue
- English
- Weight
- 288 KB
- Volume
- 146
- Category
- Article
- ISSN
- 0022-4596
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✦ Synopsis
Previous X-ray crystal structure re5nement of GaAsO 4 gave spurious As}O (1.72 A > ) and Ga-O (1.77 A > ) bond distances by comparison with theoretical values and with experimental values from AlAsO 4 and GaPO 4 ([As}O]: :1.67 A > and [Ga}O] : :1.82 A > ). Therefore, a complete structural reinvestigation of gallium arsenate was carried out between 15 and 1073 K by both neutron and X-ray di4raction. All new analyses led to experimental bond values in agreement with those predicted, i.e., close to 1.67 and 1.82 A > . This new structural investigation of GaAsO 4 over a wide range of temperatures emphasizes the high thermal stability of the -quartz packing in this compound, the best amongst quartz-like materials. The experimental relation between structural deformation and piezoelectric properties of these quartz-like materials also allows us to predict that GaAsO 4 would have the best piezoelectric characteristics for its AT-cut. Conversely, its higher covalent character should imply a greater pressure sensitivity, with a crystal structure transition around 9 GPa. Thus, GaAsO 4 would be the best piezoelectric candidate for high temperature applications but not for high pressure devices.