Relaxed Excited State Geometries in a Peierls-hubbard Model for Polyenes
نویسنده
چکیده
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 (1Ag) and triplet (1Bu) ground states, the singlet one (n Bu) and two (2 Ag) photon gaps, and the triplet one (n Ag) 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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