Abstract:
We present a method to calculate dielectric and refractivity virial coefficients using the path-integral Monte Carlo formulation of quantum statistical mechanics and validate it by comparing our results with equivalent calculations in the literature and with more traditional quantum calculations based on wavefunctions. We use state-of-the-art pair potentials and polarizabilities to calculate the second dielectric and refractivity virial coefficients of helium (both 3He and 4He), neon (both 20Ne and 22Ne), and argon. Our calculations extend to temperatures as low as 1 K for helium, 4 K for neon, and 50 K for argon. We estimate the contributions to the uncertainty of the calculated dielectric virial coefficients for helium and argon, finding that the uncertainty of the pair polarizability is by far the greatest contribution. Agreement with the limited experimental data available is generally good, but our results have smaller uncertainties, especially for helium. Our approach can be generalized in a straightforward manner to higher-order coefficients.
摘要:
我们提出了一种使用量子统计力学的路径积分蒙特卡罗公式计算介电和折射率维里系数的方法,并通过将我们的结果与文献中的等效计算以及基于波函数的更传统的量子计算进行比较来验证。我们使用最先进的成对电势和极化率来计算氦的第二介电和折射率维里系数(3He和4He),霓虹灯(20Ne和22Ne),还有氩气.我们的计算扩展到氦气的温度低至1K,4K为霓虹灯,氩气为50K。我们估算了氦气和氩气的介电维里系数对不确定性的影响,发现对极化率的不确定性是迄今为止最大的贡献。与有限的实验数据达成一致通常是好的,但是我们的结果不确定性较小,尤其是氦气。我们的方法可以直接推广到高阶系数。