Richardson-Gaudin States

Paul Andrew Johnson

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arXiv · 2312.08804

Richardson-Gaudin States

Paul Andrew Johnson

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Abstract

This chapter gives an overview of Richardson-Gaudin states which represent weakly correlated pairs of electrons. They are parametrized by sets of numbers obtained from non-linear equations. The best method to solve these equations is presented in a straightforward manner with enough detail to implement the method computationally. Optimal expressions for the density matrix elements are discussed. A simple description of 1-dimensional hydrogen chains is presented in terms of Richardson-Gaudin states. Richardson-Gaudin states are placed in the larger context of integrable models and geminal wavefunctions of quantum chemistry.

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Paul Andrew Johnson. 2023-12-14. Richardson-Gaudin States. https://arxiv.org/abs/2312.08804

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