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First-principles GW-BSE excitations in organic molecules

Murilo L. Tiago·James R. Chelikowsky
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Abstract

We present a first-principles method for the calculation of optical excitations in nanosystems. The method is based on solving the Bethe-Salpeter equation (BSE) for neutral excitations. The electron self-energy is evaluated within the GW approximation, with dynamical screening effects described within time-dependent density-functional theory in the adiabatic, local approximation. This method is applied to two systems: the benzene molecule, C$_6$H$_6$, and azobenzene, C$_{12}$H$_{10}$N$_2$. We give a description of the photoisomerization process of azobenzene after an $n-π^\star$ excitation, which is consistent with multi-configuration calculations.

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Murilo L. Tiago, James R. Chelikowsky. 2005-08-26. First-principles GW-BSE excitations in organic molecules. https://doi.org/10.1016/j.ssc.2005.08.012

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