超高压下碳结构的第一性原理研究  

First principle studies of carbon structure under super-high pressure

作　　者：姚平坤[1] 温斌[1] 赵纪军[1] 张兴国[1] 

机构地区：[1]大连理工大学三束材料改性国家重点实验室

出　　处：《原子与分子物理学报》2008年第1期53-58,共6页Journal of Atomic and Molecular Physics

基　　金：国家自然科学基金(50402025,50772018);教育部新世纪优秀人才支持计划(NCET-07-0139,NECT-06-0281)

摘　　要：采用第一性原理密度泛函理论,结合平面波赝势和广义梯度近似(GGA)方法计算了多种碳结构在超高压条件下的热力学稳定性及晶体结构性质.计算结果表明,碳结构的质量密度和基态能量与其对称性高低没有很强的依赖关系;在超高压条件下,随着压强的增加,热力学相对稳定的碳结构依次是石墨、金刚石、BC-8和SC碳结构,Clark等人所提出的R8结构并不是一种真正的高压稳定碳结构.Thermodynamic relative stability and crystal structure properties for different carbon structures are studied by using density functional theory and plane - wave pseudopotential technique with generalized gradient approximation, and the following results are obtained. There is no strong dependence relation between the crystal structure symmetry and ground energy or mass density of carbon structure. With increase of pressure, the relative stability sequences for carbon structure are graphite, diamond, BC- 8 and SC structure in turn. The R8 structure of Clark et al is not a true stability phase under high pressure.

关 键 词：碳材料 高压 晶体结构 密度泛函理论 

分 类 号：O521.2[理学—高压高温物理]