Non-orthogonal determinants in multi-Slater-Jastrow trial wave functions for fixed-node diffusion Monte Carlo
arXiv:1808.06457 · doi:10.1063/1.5052906
Abstract
The accuracy and efficiency of ab-initio quantum Monte Carlo (QMC) algorithms benefits greatly from compact variational trial wave functions that accurately reproduce ground state properties of a system. We investigate the possibility of using multi-Slater-Jastrow trial wave functions with non-orthogonal determinants by optimizing identical single particle orbitals independently in separate determinants. As a test case, we compute variational and fixed-node diffusion Monte Carlo (FN-DMC) energies of a C molecule. For a given multi-determinant expansion, we find that this non-orthogonal orbital optimization results in a consistent improvement in the variational energy and the FN-DMC energy on the order of a few tenths of an eV. Our calculations indicate that trial wave functions with non-orthogonal determinants can improve computed energies in a QMC calculation when compared to their orthogonal counterparts.
References in corpus (12)
- Low-energy spectrum of iron-sulfur clusters directly from many-particle quantum mechanics
- Optimization of quantum Monte Carlo wave functions by energy minimization
- Beyond the locality approximation in the standard diffusion Monte Carlo method
- Full optimization of Jastrow-Slater wave functions with application to the first-row atoms and homonuclear diatomic molecules
- Energetics and Dipole Moment of Transition Metal Monoxides by Quantum Monte Carlo
- Symmetry-projected Wave Functions in Quantum Monte Carlo Calculations
- Multi-component symmetry-projected approach for molecular ground state correlations
- Simple formalism for efficient derivatives and multi-determinant expansions in quantum Monte Carlo
- Quantum Monte Carlo with Jastrow-valence-bond wave functions
- Accurate nonrelativistic ground-state energies of 3d transition metal atoms
- Auxiliary-field quantum Monte Carlo study of TiO and MnO molecules
- Compact wavefunctions from compressed imaginary time evolution