Tuning of the CDW in the Halogen-Bridged Transition-Metal Linear-Chain Compounds
نویسنده
چکیده
Local-density-approximation calculations are used to show that the metal-metal distance along the chains controls the charge-density wave (CDW) in halogen-bridged transition-metal linear-chain (MX) compounds. The strength of the CDW can be understood in terms of a two band Su-Schrieffer-Heeger model if a hard-core ion-ion repulsion potential is also added. We predict a second-order phase transition from an insulating to a semi-metallic ground state and explain trends in dimerization, bondlength ratios, band gaps, and Raman breathing modes in terms of the metal-metal distance.
منابع مشابه
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