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arXiv · 2307.00560

Economical Quasi-Newton Self Consistent Field Solver

Samuel A. Slattery·Kshitijkumar Surjuse·Edward F. Valeev
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Abstract

We present an efficient quasi-Newton orbital solver optimized to reduce the number of gradient (Fock matrix) evaluations. The solver optimizes orthogonal orbitals by sequences of unitary rotations generated by the (preconditioned) limited-memory Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) algorithm incorporating trust-region step restriction. Low-rank structure of the inverse (approximate) Hessian is exploited not only in L-BFGS but also when solving the trust-region problem. The efficiency of the proposed ``Quasi-Newton Unitary Optimization with Trust-Region'' (QUOTR) method is compared to that of the standard Roothaan-Hall approach accelerated by the Direct Inversion of Iterative Subspace (DIIS), and other exact and approximate Newton solvers for mean-field (Hartree-Fock and Kohn-Sham) problems.

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Samuel A. Slattery, Kshitijkumar Surjuse, Edward F. Valeev. 2023-07-02. Economical Quasi-Newton Self Consistent Field Solver. https://doi.org/10.1039/d3cp05557d

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