摘要
从RDX炸药分子结构出发,运用电子结构理论、分子间微扰理论等第一性原理获得了α-RDX炸药全原子自洽力场(selfconsistent force field,SC FF)。基于SC FF,进一步发展出自洽力场—声子(SC FF-phonon)非谐自由能计算方法。该方法能较好考虑固体炸药的声子非谐效应以及核的量子效应。通过非谐自由能计算方法,获得了常压到55 GPa范围内等熵加载线及其热力学性质。等熵加载线的p(GPa)-V(cm^3/m ol)和T(K)~V(cm^3/m ol)数学关系分别为:p=66.59633+4.52375 exp(-V/0.68117)+16.56087exp(-V/4.31486)+35.94539exp(-V/32.26906)和lnT=5.06548+0.74774ln V-0.13886(lnV)~2。自洽力场方法和SCFF!phonon计算方法可为炸药状态方程构建及热力学等物性数据计算提供行之有效的理论工具。
Starting with the molecular structure of α-RDX, the non-empirical full atom self-consistent force field (SCFF) for the explosive was derived via the first principles including electronic structure theory, intermolecular perturbation theory, and based on the SCFF-phonon approach to calculating the anharmonic free energy, the isentropic locus for α-RDX was obtained, covering a pressure range from the ambient pressure to 55 GPa. The relationships between p(GPa)and V(cm^3·mol^-1), and between T(K) and V(cm^3·mol^-1) of the isentropic locus are: p=66.59633+4.52375exp(-V/0.68117)+16.56087exp(-V/4.31486)+35.94539exp(-V/32.26906) and lnT=5.06548+0.74774lnV-0.13886(lnV)^2 , respectively. The SCFF and SCFF-phonon methods can be generalized toward other high energetic materials and thus provides an effective theoretical tool for constructing their precise EOSs and computing thermodynamic properties.
出处
《含能材料》
EI
CAS
CSCD
北大核心
2018年第1期53-58,共6页
Chinese Journal of Energetic Materials
基金
科学挑战专题(TZ2016001)
国家自然科学基金资助(11372053)
北京理工大学爆炸科学与技术国家重点实验室开放基金(KFJJ16-01M)
关键词
状态方程
热力学性质
声子
原子作用势
炸药
equation of state
thermodynamic properties
phonon
atomic potential
explosive