Quadratic accuracy diffusion Monte Carlo (Q1071485)

We derive a Monte Carlo Green function with a quadratic time-step bias, and point out the importance of properly simulating the discontinuities of the drift function at the nuclei. We suggest that for small atoms and molecules, where the nodes in the trial function are well separated, our algorithm enables one to use large time steps, thus gaining in precision of the ground-energy estimate by dramatically reducing the serial correlation of consecutive iterations.