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arXiv · 2404.14655

Geometric Optimization of Restricted-Open and Complete Active Space Self-Consistent Field Wavefunctions

Laurent Vidal·Tommaso Nottoli·Filippo Lipparini·Eric Cancès
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Abstract

We explore Riemannian optimization methods for Restricted-Open-shell Hartree-Fock (ROHF) and Complete Active Space Self-Consistent Field (CASSCF) methods. After showing that ROHF and CASSCF can be reformulated as optimization problems on so-called flag manifolds, we review Riemannian optimization basics and their application to these specific problems. We compare these methods to traditional ones and find robust convergence properties without fine-tuning of numerical parameters. Our study suggests Riemannian optimization as a valuable addition to orbital optimization for ROHF and CASSCF, warranting further investigation.

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Laurent Vidal, Tommaso Nottoli, Filippo Lipparini, Eric Cancès. 2024-04-23. Geometric Optimization of Restricted-Open and Complete Active Space Self-Consistent Field Wavefunctions. https://arxiv.org/abs/2404.14655

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