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Franck-Condon Factors as Spectral Probes of Polaron Structure

David W. Brown·Aldo H. Romero·Katja Lindenberg
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Abstract

We apply the Merrifield variational method to the Holstein molecular crystal model in D dimensions to compute non-adiabatic polaron band energies and Franck-Condon factors at general crystal momenta. We analyze these observable properties to extract characteristic features related to polaron self-trapping and potential experimental signatures. These results are combined with others obtained by the Global-Local variational method in 1D to construct a polaron phase diagram encompassing all degrees of adiabaticity and all electron-phonon coupling strengths. The polaron phase diagram so constructed includes disjoint regimes occupied by "small" polarons, "large" polarons, and a newly-defined class of "compact" polarons, all mutually separated by an intermediate regime occupied by transitional structures.

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David W. Brown, Aldo H. Romero, Katja Lindenberg. 1999-06-16. Franck-Condon Factors as Spectral Probes of Polaron Structure. https://doi.org/10.1021/jp992035v

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