Moroni S, Pederiva F, Fantoni S, Boninsegni M
INFM, Universita di Roma La Sapienza, Roma, Italy.
Phys Rev Lett. 2000 Mar 20;84(12):2650-3. doi: 10.1103/PhysRevLett.84.2650.
We present results of diffusion Monte Carlo calculations for the bcc and hcp phases of solid 3He, using a recent ab initio interatomic potential, including two- and three-body terms. This potential is found to yield an equation of state for condensed 4He in excellent agreement with experiment, in a wide density range. For 3He, we find a systematic discrepancy, worth 0.7 K, between our computed equation of state and a commonly accepted experimental one. We attribute such a discrepancy to an improper choice of reference energy in the determination of the experimental equation of state.
我们展示了使用最近的包含两体和三体项的从头算原子间势对固态³He的体心立方（bcc）相和面心立方（hcp）相进行扩散蒙特卡罗计算的结果。发现该势在很宽的密度范围内给出的凝聚态⁴He的状态方程与实验结果高度吻合。对于³He，我们发现在计算得到的状态方程与一个普遍接受的实验状态方程之间存在0.7 K的系统偏差。我们将这种偏差归因于在确定实验状态方程时参考能量的选择不当。
