Dataset Information

Linear Response Equations Revisited: A Simple and Efficient Iterative Algorithm.

ABSTRACT: We present an algorithm to solve the linear response equations for Hartree-Fock, Density Functional Theory, and the Multiconfigurational Self-Consistent Field method that is both simple and efficient. The algorithm makes use of the well-established symmetric and antisymmetric combinations of trial vectors but further orthogonalizes them with respect to the scalar product induced by the response matrix. This leads to a standard, symmetric block eigenvalue problem in the expansion subspace that can be solved by diagonalizing a symmetric, positive definite matrix half the size of the expansion space. Numerical tests showed that the algorithm is robust and stable.

SUBMITTER: Alessandro R

PROVIDER: S-EPMC10753806 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature

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Linear Response Equations Revisited: A Simple and Efficient Iterative Algorithm.

Alessandro Riccardo R Giannì Ivan I Pes Federica F Nottoli Tommaso T Lipparini Filippo F

Journal of chemical theory and computation 20231211 24

We present an algorithm to solve the linear response equations for Hartree-Fock, Density Functional Theory, and the Multiconfigurational Self-Consistent Field method that is both simple and efficient. The algorithm makes use of the well-established symmetric and antisymmetric combinations of trial vectors but further orthogonalizes them with respect to the scalar product induced by the response matrix. This leads to a standard, symmetric block eigenvalue problem in the expansion subspace that ca ...[more]

PMID: 38081062

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Dataset Information

Linear Response Equations Revisited: A Simple and Efficient Iterative Algorithm.

Publications

Linear Response Equations Revisited: A Simple and Efficient Iterative Algorithm.

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