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Nonlinear lattice relaxation of photoexcited diplatinum-halide chain compounds

Jun Ohara·Shoji Yamamoto
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Abstract

In order to reveal the relaxation mechanism of photogenerated charge-transfer excitations in quasi-one-dimensional halogen-bridged diplatinum complexes, we calculate the low-lying adiabatic potential energy surfaces of a one-dimensional extended Peierls-Hubbard model. High-energy excitations above the electron-hole continuum may relax into polarons, while excitons pumped within the optical gap are self-localized and then either decay by luminescence or divide into solitons. Neutral solitons, charged solitons, and polarons may be simultaneously photogenerated in a diplatinum-halide chain, which has never been observed in any conventional platinum-halide chain. Optical conductivity is also simulated along the decay paths for experimental verification.

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Jun Ohara, Shoji Yamamoto. 2005-12-24. Nonlinear lattice relaxation of photoexcited diplatinum-halide chain compounds. https://doi.org/10.1103/physrevb.73.045122

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