Newton optimization for the Multiconfiguration Self Consistent Field method at the basis set limit: closed-shell two-electron systems

Evgueni Dinvay; Rasmus Vikhamar-Sandberg

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arXiv · 2506.12906

Newton optimization for the Multiconfiguration Self Consistent Field method at the basis set limit: closed-shell two-electron systems

Evgueni Dinvay·Rasmus Vikhamar-Sandberg

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Abstract

The multiconfiguration self-consistent field (MCSCF) method is revisited with a specific focus on two-electron systems for simplicity. The wave function is represented as a linear combination of Slater determinants. Both the orbitals and the coefficients of this configuration interaction expansion are optimized according to the variational principle within the Lagrangian formalism, using a Newton optimization scheme. This reduces the MCSCF problem to solving a particular differential Newton system, which can be discretized with multiwavelets and solved iteratively.

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Evgueni Dinvay, Rasmus Vikhamar-Sandberg. 2025-06-15. Newton optimization for the Multiconfiguration Self Consistent Field method at the basis set limit: closed-shell two-electron systems. https://arxiv.org/abs/2506.12906

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