摘要
用分子动力学模拟和与固氦实验等温线比较的方法,确定了高密度氦指数6势函数中劲度系数α的优选值为12.7。然后我们用这个新的α值计算了fcc固氦的状态方程及其径向分布函数,发现当把ρ限定为1.60g/cm3时,其径向分布函数的第二个峰将在2000K到3040K区间消失,表明此时固氦的长程有序性降低,或者说发生了固液相变过程。
The optimized value of α =12.7,which is the stiffness parameter in exponential 6 potential function used for describing the compression behavior of dense helium,is determined by means of molecular dynamics simulation and makes comparison with the experimental isotherm of solid helium.Then,we adopte this new value of α to calculate the equation of state and the radial distribution function for fcc solid helium at high temperatures,and find while ρ =1.60g/cm 3 the second peak of the radial distribution function would disappear in the regime of 2000K to 3040K.It demonstrates the long range degree of order is degraded or the solid liquid transition occurrs under that condition.
出处
《高压物理学报》
CAS
CSCD
北大核心
1999年第4期255-261,共7页
Chinese Journal of High Pressure Physics
基金
中国工程物理研究院科学技术基金!重点资助项目 ( 97Z0 11)
关键词
指数6势
分子动力学模拟
氦
高密度
状态方程
exponential 6 potential
molecular dynamics simulation
radial distribution function
