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Relaxed Excited State Geometries in a Peierls-Hubbard Model for Polyenes

J. Tinka Gammel·D. K. Campbell
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Abstract

Using parameter values relevant to polyacetylene and its finite polyene analogs, we determine, via exact finite size diagonalization of a 1D Peierls-Hubbard model, the relaxed geometry and optical absorption spectra of several states of interest in optical experiments (the singlet ($1^1A_g$) and triplet ($1^3B_u$) ground states, the singlet one ($n^1B_u$) and two ($2^1A_g$) photon gaps, and the triplet one ($n^3A_g$) photon gap) in order to examine the question of how well this simple model can really capture the behavior of this simple material.

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J. Tinka Gammel, D. K. Campbell. 1992-09-18. Relaxed Excited State Geometries in a Peierls-Hubbard Model for Polyenes. https://arxiv.org/abs/cond-mat/9209025

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