TY - JOUR
T1 - Zone-center modes of cubic and hexagonal diamond under high pressure
T2 - a first-principles study
AU - Wu, B. R.
AU - Xu, J.
PY - 1999
Y1 - 1999
N2 - The high-pressure behavior of the optical modes of the cubic and hexagonal diamond at the Brillouin-zone center is studied with a first-principles method. In addition, the Grüneisen parameters of the cubic and hexagonal diamond are obtained. It is found that most of the phonon frequencies of the cubic and hexagonal diamond exhibit blueshift under pressure except for the (Formula presented) mode of the hexagonal diamond, which is softening above 42 GPa. Therefore, a phase transformation of the hexagonal diamond at high pressure is expected. The Grüneisen parameters of the (Formula presented) and (Formula presented) modes are quite close to that of the (Formula presented) mode of the cubic diamond.
AB - The high-pressure behavior of the optical modes of the cubic and hexagonal diamond at the Brillouin-zone center is studied with a first-principles method. In addition, the Grüneisen parameters of the cubic and hexagonal diamond are obtained. It is found that most of the phonon frequencies of the cubic and hexagonal diamond exhibit blueshift under pressure except for the (Formula presented) mode of the hexagonal diamond, which is softening above 42 GPa. Therefore, a phase transformation of the hexagonal diamond at high pressure is expected. The Grüneisen parameters of the (Formula presented) and (Formula presented) modes are quite close to that of the (Formula presented) mode of the cubic diamond.
UR - http://www.scopus.com/inward/record.url?scp=0000339252&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.60.2964
DO - 10.1103/PhysRevB.60.2964
M3 - 文章
AN - SCOPUS:0000339252
SN - 1098-0121
VL - 60
SP - 2964
EP - 2967
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
IS - 5
ER -