Ma A, Towler M D, Drummond N D, Needs R J
Theory of Condensed Matter Group, Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE, United Kingdom.
J Chem Phys. 2005 Jun 8;122(22):224322. doi: 10.1063/1.1940588.
A simple scheme is described for introducing the correct cusps at nuclei into orbitals obtained from Gaussian basis set electronic structure calculations. The scheme is tested with all-electron variational quantum Monte Carlo (VMC) and diffusion quantum Monte Carlo (DMC) methods for the Ne atom, the H2 molecule, and 55 molecules from a standard benchmark set. It greatly reduces the variance of the local energy in all cases and slightly improves the variational energy. This scheme yields a general improvement in the efficiency of all-electron VMC and DMC calculations using Gaussian basis sets.
描述了一种简单的方案，用于将原子核处的正确尖点引入通过高斯基组电子结构计算获得的轨道中。该方案通过全电子变分量子蒙特卡罗（VMC）和扩散量子蒙特卡罗（DMC）方法对Ne原子、H₂分子以及来自标准基准集的55个分子进行了测试。在所有情况下，它都大大降低了局部能量的方差，并略微提高了变分能量。该方案总体上提高了使用高斯基组的全电子VMC和DMC计算的效率。
