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Novel Density-Wave States of Two-Band Peierls-Hubbard Chains

Shoji Yamamoto
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Abstract

Based on a symmetry argument we systematically reveal Hartree-Fock broken-symmetry solutions of the one-dimensional two-band extended Peierls-Hubbard model, which covers various materials of interest such as halogen-bridged metal complexes and mixed-stack charge-transfer salts. We find out all the regular-density-wave solutions with an ordering vector $q=0$ or $q=π$. Changing band filling as well as electron-electron and electron-phonon interactions, we numerically inquire further into the ground-state phase diagram and the physical property of each state. The possibility of novel density-wave states appearing is argued.

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Shoji Yamamoto. 1998-06-28. Novel Density-Wave States of Two-Band Peierls-Hubbard Chains. https://doi.org/10.1016/s0375-9601(98)00612-4

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