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arXiv · 0901.3052

Photo-excitation of a light-harvesting supra-molecular triad: a Time-Dependent DFT study

N. Spallanzani·C. A. Rozzi·D. Varsano·T. Baruah·M. R. Pederson·F. Manghi·A. Rubio
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Abstract

We present the first time-dependent density-functional theory (TDDFT) calculation on a light harvesting triad carotenoid-diaryl-porphyrin-C60. Besides the numerical challenge that the ab initio study of the electronic structure of such a large system presents, we show that TDDFT is able to provide an accurate description of the excited state properties of the system. In particular we calculate the photo-absorption spectrum of the supra-molecular assembly, and we provide an interpretation of the photo-excitation mechanism in terms of the properties of the component moieties. The spectrum is in good agreement with experimental data, and provides useful insight on the photo-induced charge transfer mechanism which characterizes the system.

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N. Spallanzani, C. A. Rozzi, D. Varsano, T. Baruah, M. R. Pederson, F. Manghi, A. Rubio. 2009-03-12. Photo-excitation of a light-harvesting supra-molecular triad: a Time-Dependent DFT study. https://arxiv.org/abs/0901.3052

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