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On the possibility to use non-orthogonal orbitals for Density Matrix Renormalization Group calculations in Quantum Chemistry

A. O. Mitrushenkov·Guido Fano·Roberto Linguerri·Paolo Palmieri
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Abstract

The generalization of Density Matrix Renormalization Group (DMRG) approach as implemented in quantum chemistry, to the case of non-orthogonal orbitals is carefully analyzed. This generalization is attractive from the physical point of view since it allows a better localization of the orbitals. The possible implementation difficulties and drawbacks are estimated. General formulae for hamiltonian matrix elements useful in DMRG calculations are given.

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A. O. Mitrushenkov, Guido Fano, Roberto Linguerri, Paolo Palmieri. 2003-06-03. On the possibility to use non-orthogonal orbitals for Density Matrix Renormalization Group calculations in Quantum Chemistry. https://arxiv.org/abs/cond-mat/0306058

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