Pachucki Krzysztof, Komasa Jacek
Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland.
Phys Chem Chem Phys. 2017 Dec 20;20(1):247-255. doi: 10.1039/c7cp06516g.
We present a new computational method for the determination of energy levels in four-particle systems like H, HD, and HeH using explicitly correlated exponential basis functions and analytic integration formulas. In solving the Schrödinger equation, no adiabatic separation of the nuclear and electronic degrees of freedom is introduced. We provide formulas for the coupling between the rotational and electronic angular momenta, which enable calculations of arbitrary rotationally excited energy levels. To illustrate the high numerical efficiency of the method, we present the results for various states of the hydrogen molecule. The relative accuracy to which we determined the nonrelativistic energy reached the level of 10-10, which corresponds to an uncertainty of 10-10 cm.
我们提出了一种新的计算方法，用于确定诸如H、HD和HeH等四粒子系统中的能级，该方法使用显式相关的指数基函数和解析积分公式。在求解薛定谔方程时，未引入核自由度和电子自由度的绝热分离。我们提供了转动角动量和电子角动量之间耦合的公式，这使得能够计算任意转动激发能级。为了说明该方法的高数值效率，我们给出了氢分子各种状态的结果。我们确定的非相对论能量的相对精度达到了10^-10的水平，这对应于10^-10 cm的不确定性。
