The Journal of Physical Chemistry Letters 4, 4206-4212 (2013)

Toward Ab Initio Optical Spectroscopy of the Fenna-Matthews-Olson Complex

Daniel J. Cole^1,2, Alex W. Chin¹, Nicholas D. M. Hine^1,3, Peter D. Haynes³ and Mike C. Payne¹

¹TCM Group, Cavendish Laboratory, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
²Department of Chemistry, Yale University, 225 Prospect Street, New Haven, Connecticut 06250-8107, United States
³Departments of Materials and Physics, Imperial College London, Exhibition Road, London SW7 2AZ, United Kingdom

We present progress toward a first-principles parametrization of the Hamiltonian of the Fenna-Matthews-Olson pigment–protein complex, a molecule that has become key to understanding the role of quantum dynamics in photosynthetic exciton energy transfer. To this end, we have performed fully quantum mechanical calculations on each of the seven bacteriochlorophyll pigments that make up the complex, including a significant proportion of their protein environment (more than 2000 atoms), using linear-scaling density functional theory exploiting a recent development for the computation of excited states. Local pigment transition energies and interpigment coupling between optical transitions have been calculated and are in good agreement with the literature consensus. Comparisons between simulated and experimental optical spectra point toward future work that may help to elucidate important design principles in these nanoscale devices.

Last updated: 29 November 2013