Pfaffian pairing wave functions in electronic-structure quantum Monte Carlo simulations |
| |
Authors: | Bajdich M Mitas L Drobný G Wagner L K Schmidt K E |
| |
Institution: | Center for High Performance Simulation and Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, USA. |
| |
Abstract: | We investigate the accuracy of trial wave functions for quantum Monte Carlo based on Pfaffian functional form with singlet and triplet pairing. Using a set of first row atoms and molecules we find that these wave functions provide very consistent and systematic behavior in recovering the correlation energies on the level of 95%. In order to get beyond this limit we explore the possibilities of multi-Pfaffian pairing wave functions. We show that a small number of Pfaffians recovers another large fraction of the missing correlation energy comparable to the larger-scale configuration interaction wave functions. We also find that Pfaffians lead to substantial improvements in fermion nodes when compared to Hartree-Fock wave functions. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|