Hamiltonian symmetries in auxiliary-field quantum Monte Carlo calculations for electronic structure
Abstract
We describe how to incorporate symmetries of the Hamiltonian into auxiliary-field quantum Monte Carlo (AFQMC) calculations. Focusing on the case of Abelian symmetries, we show that the computational cost of most steps of an AFQMC calculation is reduced by Nk-1, where Nk is the number of irreducible representations of the symmetry group. We apply the formalism to a molecular system as well as to several crystalline solids. In the latter case, the lattice translational group provides increasing savings as the number of k points is increased, which is important in enabling calculations that approach the thermodynamic limit. The extension to non-Abelian symmetries is briefly discussed.
- Publication:
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Physical Review B
- Pub Date:
- July 2019
- DOI:
- 10.1103/PhysRevB.100.045127
- arXiv:
- arXiv:1905.00511
- Bibcode:
- 2019PhRvB.100d5127M
- Keywords:
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- Physics - Computational Physics;
- Physics - Chemical Physics
- E-Print:
- 13 pages, 7 figures