中國有色金屬學報(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 21 No. 6 June 2011 |
YZnAsO and LaZnAsO investigated by first principles
（1. Department of Basic Teaching, Hunan Institute of Technology, Hengyang 421000, China;
2. School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China）
Abstract:The structural parameters, chemical bonding and elastic properties of the tetragonal phase quaternary arsenide oxides YZnAsO and LaZnAsO were investigated by using density-functional theory (DFT) within generalized gradient approximation (GGA). The GGA calculated structural parameters are in agreement with the experimental results. Population analysis suggests that the chemical bonding in YZnAsO and LaZnAsO can be classified as a mixture of ionic and covalent characteristic. Single-crystal elastic constants were calculated and the polycrystalline elastic modules were estimated according to Voigt, Reuss and Hill’s approximations (VRH). The result shows that both YZnAsO and LaZnAsO are relatively soft materials exhibiting ductile behavior. The calculated polycrystalline elastic anisotropy result shows that LaZnAsO is more anisotropy in compressibility and YZnAsO is more anisotropy in shear.
Key words: YZnAsO; LaZnAsO; chemical bonding; elastic properties; density-functional theory; generalized gradient approximation; Voigt, Reuss and Hill’s approximations
