Efficient implementation of the Hellmann-Feynman theorem in a diffusion Monte Carlo calculation

摘要

Kinetic and potential energies of systems of ~4He atoms in the solid phase are computed at T = 0. Results at two densities of the liquid phase are presented as well. Calculations are performed by the multiweight extension to the diffusion Monte Carlo method that allows the application of the Hellmann-Feynman theorem in a robust and efficient way. This is a general method that can be applied in other situations of interest as well.