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Characterization of halogen-bridged binuclear metal complexes as hybridized two-band materials

Shoji Yamamoto
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Abstract

We study the electronic structure of halogen-bridged binuclear metal (MMX) complexes with a two-band Peierls-Hubbard model. Based on a symmetry argument, various density-wave states are derived and characterized. The ground-state phase diagram is drawn within the Hartree-Fock approximation, while the thermal behavior is investigated using a quantum Monte Carlo method. All the calculations conclude that a typical MMX compound Pt_2(CH_3CS_2)_4I should indeed be regarded as a d-p-hybridized two-band material, where the oxidation of the halogen ions must be observed even in the ground state, whereas another MMX family (NH_4)_4[Pt_2(P_2O_5H_2)_4X] may be treated as single-band materials.

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Shoji Yamamoto. 2001-01-01. Characterization of halogen-bridged binuclear metal complexes as hybridized two-band materials. https://doi.org/10.1103/physrevb.63.125124

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