摘要
The phase transitions of semiconductor CaN from the Wurtzite （WZ） structure and the zinc-blende （ZB） structure to the rocksalt （R,S） structure are investigated by using the first-principles plane-wave pseudopotential density functional method combined with the ultrasoft pseudopotentied scheme in the generalized gradient approximation （GGA） correction. It is found that the phase transitions from the WZ structure and the ZB structure to the R,S structure occur at pressures of 46.1 GPa and 45.2 GPa, respectively. The lattice parameters, bulk moduli and their pressure derivatives of these structures of CaN are also calculated. Our results are consistent with available experimental and other theoretical results. The dependence of the normalized formula-unit volume V/V0 on pressure P is also successfully obtained.
The phase transitions of semiconductor CaN from the Wurtzite （WZ） structure and the zinc-blende （ZB） structure to the rocksalt （R,S） structure are investigated by using the first-principles plane-wave pseudopotential density functional method combined with the ultrasoft pseudopotentied scheme in the generalized gradient approximation （GGA） correction. It is found that the phase transitions from the WZ structure and the ZB structure to the R,S structure occur at pressures of 46.1 GPa and 45.2 GPa, respectively. The lattice parameters, bulk moduli and their pressure derivatives of these structures of CaN are also calculated. Our results are consistent with available experimental and other theoretical results. The dependence of the normalized formula-unit volume V/V0 on pressure P is also successfully obtained.
基金
Project supported by the National Natural Science Foundation of China （Grant No 10576020）.
