Orthorhombic intermediate state in the zinc blende to rocksalt transformation path of SiC at high pressure

被引：112

作者：

Catti, M ^{[1
]}

机构：

[1] Univ Milano Bicocca, Dipartimento Sci Mat, I-20125 Milan, Italy

来源：

PHYSICAL REVIEW LETTERS | 2001年 / 87卷 / 03期

关键词：

D O I：

10.1103/PhysRevLett.87.035504

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

The mechanism of the B3/B1 phase transition of SiC has been investigated by periodic LCAO-DFT least-enthalpy calculations. A new transformation pathway, based on a Pmm2 orthorhombic intermediate slate with two SiC units per cell, is found to be energetically favored over the traditional R3m mechanism. The computed activation enthalpy is 0.75 eV/SiC unit at the predicted transition pressure of 92 GPa (B3LYP functional). Activation enthalpy and activation volume vs pressure are analyzed to characterize the kinetic aspects of the transformation.

引用

页码：35504 / 1

页数：4

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