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.
@article{arxiv.0901.3052,
title = {Photo-excitation of a light-harvesting supra-molecular triad: a Time-Dependent DFT study},
author = {N. Spallanzani and C. A. Rozzi and D. Varsano and T. Baruah and M. R. Pederson and F. Manghi and A. Rubio},
journal= {arXiv preprint arXiv:0901.3052},
year = {2009}
}