Speed-up of hybrid Monte Carlo and path integral hybrid Monte Carlo simulations by using an auxiliary potential energy surface

Nakayama, Akira*; Taketsugu, Tetsuya*; Shiga, Motoyuki   

Efficiency of the ab initio hybrid Monte Carlo and path integral hybrid Monte Carlo methods is enhanced by employing an auxiliary potential energy surface that is used to update the system configuration via molecular dynamics scheme. As a simple illustration of this method, a dual-level approach is introduced where potential energy gradients are evaluated by computationally less expensive ab initio electronic structure methods.