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Europhysics Letters (EPL)

Quantum-molecular-dynamics calculation of the density of states and electrical conductivity: application to the soliton model for polyacetylene

Kristel F. L. Michielsen, Hans A. De Raedt

Published May 20, 1996• 5 citations
Publisher

Abstract

We present a simulation method to compute the time-dependent properties of a system of fermions coupled to classical degrees of freedom. The method is employed to calculate the static and dynamic properties of the Su-Schrieffer-Heeger model for polyacetylene chains. Our results for the static quantities for chains, containing up to 256 electrons on 256 sites, are in excellent agreement with previous work and confirm that solitons are only present for very small doping. Our simulation data for the optical absorption as a function of dopant concentration are in good agreement with experiment.

DOI
10.1209/epl/i1996-00475-5

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We present a simulation method to compute the time-dependent properties of a system of fermions coupled to classical degrees of freedom. The method is employed to calculate the static and dynamic properties of the Su-Schrieffer-Heeger model for polyacetylene chains. Our results for the static quantities for chains, containing up to 256 electrons on 256 sites, are in excellent agreement with previous work and confirm that solitons are only present for very small doping. Our simulation data for the optical absorption as a function of dopant concentration are in good agreement with experiment.
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