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Electron localization in one dimension obtained from combined exact diagonalization - ab initio approach

Jozef Spalek·Adam Rycerz
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Abstract

Exact ground-state properties are presented by combining the diagonalization in the Fock space (and taking all hopping integrals and all two-site interactions) with the ab initio optimization of the Wannier functions. Electrons are essentially localized for the interatomic distance R~2A for s-like states, when the quasiparticle mass is divergent. The momentum distribution dispersion is proposed to define the localization order parameter. Dimerization and zero-point energies are also discussed. The method provides convergent results for N>=8 atoms.

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Jozef Spalek, Adam Rycerz. 2001-06-05. Electron localization in one dimension obtained from combined exact diagonalization - ab initio approach. https://doi.org/10.1103/physrevb.64.161105

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