Interdisciplinary Laboratory for Computational Science (LISC), FBK-CMM and University of Trento, Povo (TN), Italy.
J Chem Phys. 2011 Apr 7;134(13):134106. doi: 10.1063/1.3573564.
We derive path-integral expressions for the second and third virial coefficients of monatomic quantum gases. Unlike previous work that considered only Boltzmann statistics, we include exchange effects (Bose-Einstein or Fermi-Dirac statistics). We use state-of-the-art pair and three-body potentials to calculate the third virial coefficient of (3)He and (4)He in the temperature range 2.6-24.5561 K. We obtain uncertainties smaller than those of the limited experimental data. Inclusion of exchange effects is necessary to obtain accurate results below about 7 K.
我们推导出了单原子量子气体的第二和第三维里系数的路径积分表达式。与仅考虑玻尔兹曼统计的先前工作不同，我们包括了交换效应（玻色-爱因斯坦或费米-狄拉克统计）。我们使用最先进的对和三体势来计算（3）He 和（4）He 在 2.6-24.5561 K 的温度范围内的第三维里系数。我们得到的不确定度小于有限实验数据的不确定度。在大约 7 K 以下获得准确的结果，必须包括交换效应。
