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arXiv · 0708.1128

Calculations of the Exciton Coupling Elements Between the DNA Bases Using the Transition Density Cube Method

Arkadiusz Czader·Eric R. Bittner
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Abstract

Excited states of the of the double-stranded DNA model (A)$_{12}\cdot$(T)_{12} were calculated in the framework of the exciton theory. The off-diagonal elements of the exciton matrix were calculated using the transition densities and ideal dipole approximation associated with the lowest energy $ππ^{*}$ excitations of the individual nucleobases obtained from TDDFT calculations. The values of the coupling calculated with the transition density cubes (TDC) and ideal-dipole approximation (IDA) methods were found significantly different for the small inter-chromophore distances. It was shown that the IDA overestimates the coupling significantly. The effects of the structural fluctuations were incorporated by averaging the properties of the excited states over a large number of conformations obtained from the MD simulations.

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Arkadiusz Czader, Eric R. Bittner. 2007-08-08. Calculations of the Exciton Coupling Elements Between the DNA Bases Using the Transition Density Cube Method. https://doi.org/10.1063/1.2821384

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