First-principles calculations of transition phase and thermodynamic properties of CdO

The transition phase of CdO from NaCl-type (B1) structure to CsCl-type (B2) structure is investigated by ab initio plane-wave pseudopotential density-functional theory, and the thermodynamic properties of the B1 and B2 structures under high pressure and temperature are obtained through the quasiharmonic Debye model. The transition phase from B1 structure to B2 structure occurs at a pressure of 83.1 GPa, which agrees well with other calculated values. Moreover, the relationship of the relative volume V/V0, and the Debye temperature Θ and the heat capacity CV with the pressure P and temperature T are also successfully obtained. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)