Electronic excitations of biomolecules studied by quantum chemistry.

Significant methodological advances have been made over the past ten years in developing reliable quantum chemical methods for the treatment of electronically excited states. These methods can nowadays be used routinely by the experienced researcher to accurately compute excitation spectra of medium-sized organic molecules; results have been reported for several popular photobiological systems, including green fluorescent protein. First steps are currently being taken to account for the solvochromic shifts of chromophore excitations caused by particular protein environments and to dynamically simulate photochemical reactions in the excited states.