Open AccessTheoretical study of phase transition of 3C-SiC under high pressure
Author(s) -
Mengya Lu,
Zhouwen Chen,
Lixin Li,
Riping Liu,
Wenkui Wang
Publication year - 2006
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.55.3576
Subject(s) - phase transition , materials science , condensed matter physics , hysteresis , symmetry (geometry) , phase (matter) , thermodynamics , enthalpy , ferroics , transition metal , character (mathematics) , quantum phase transition , physics , quantum critical point , chemistry , quantum mechanics , biochemistry , geometry , mathematics , catalysis
Based on the generalized gradient approximation, we have investigated the phase transition of 3C-SiC from ZB to NaCl structure using first-principles method, and obtained the accurate symmetry Imm2 (previously regarded as lower symmetry Cmm2 and Pmm2) of the intermediate phase. The relative activation enthalpy 0.647eV is close to the result of Catti. The obtained transition pressure 69GPa is lower than the experimental value of 100GPa which may be attributed to the hysteresis of the phase transition. Meanwhile, the energy bands for ZB- and NaCl-SiC were also calculated and discussed, the results suggest that the phase transition of 3C-SiC is accompanied by an electronic transition from semiconducting to metallic character besides the structure reconstruction, which may be useful for the accurate determination of the transition pressure.