多体作用对氦原子团簇He9压缩特性的贡献

Many-Body Contributions for the Compressibility of Helium Atomic Cluster He9

1.
Laboratory for Shock Wave and Detonation Physics Research, Southuest Institute of Fluid Physics, Chengdu 610003, China;
2.
Institute of Applied Physics, Sichuan Union University, Chengdu 610065, China

摘要: 采用Lowdin方法计算了处于压缩状态的氦原子团簇He9体心立方向型的排斥势及其多体分量，并由此计算出团簇微观压强及其多体分压强。结果发现，多体作用对氦原子团簇He9压缩特性贡献较大。在相同体积下，由两体近似方法计算的体系压强比多原子体系实际压强偏高10%~30%；考虑三体分压强修正后，近似理论的计算值又会偏低1.5%~10%；只有同时考虑三体、四体修正后，近似理论计算值与实际多原子体系的压强值基本一致。团簇He9所表现出的压缩特性与固态氦的实验结果相符合。
- 多体作用 /
- 原子团簇 /
- 压缩特性
Abstract: Lowdin scheme was applied to calculate the repulsive potentials and their multi-body expansions of compressed atomic cluster He9. The micro-pressure and their expansions were calculated. The results show that many-body effects are important for the compressibility of atomic cluster He9. At the same volume, the pressure calculated by two-body approximation is 10%～30% higher than the actual many-body system. If three-body corrections are considered, the results become 1.5%～10% lower. When the four-body effect was included, the approximation calculations fit real system quite well. The compression properties of atomic cluster He9 are similar to the experimental results of solid helium.
- many-bordy interaction /
- atomic cluster /
- compressibility