Many-Body Contributions to Cohesive Energy of Highly Compressed Solid 4He
TIAN Chun-Ling1,3, LIU Fu-Sheng1, CAI Ling-Cang2, JING Fu-Qian1,2
1Institute of Physics, Southwest Jiaotong University, Chengdu 610031
2Laboratory of Shock Wave and Detonation Physics Research, Chinese Academy of Engineering Physics, Mianyang 621900
3Department of Physics, Southwest Normal University, Chongqing 400715
Many-Body Contributions to Cohesive Energy of Highly Compressed Solid 4He
1Institute of Physics, Southwest Jiaotong University, Chengdu 610031
2Laboratory of Shock Wave and Detonation Physics Research, Chinese Academy of Engineering Physics, Mianyang 621900
3Department of Physics, Southwest Normal University, Chongqing 400715
Abstract： A many-body expansion of cohesive energy of solid 4He is made up to five-body term, and short-range two-, three-, four- and five-body contributions have been computed by using the Hartree-Fock self-consistent-field technique and the same atomic basis set (6311G). At high densities the Hartree-Fock part of two- and four-body contributions are repulsive, whereas the three- and five-body ones are attractive. The four-body term increases as much as 15% repulsion of two-body term, and at the same time the five-body term reduces 4% of two-body repulsion at 2.5cm3/mol. The four- and five-body terms are found to be important to describe short-range inter-atomic interaction correctly and to compute the cohesive energy accurately in a wide compression range from 2.5 to 7.5cm3/mol.
2003, Vol. 20 
