An Excited State Density Functional Theory Study of the Rhodopsin Chromophore

Using a recently developed scheme for performing, within density functional theory, molecular dynamics and geometry optimization for fairly large systems in the first excited singlet state, we have studied the structure and energy changes that the rhodopsin chromophore undergoes during the photoisomerization from 11-cis to all-trans . We discuss the effects of relevant parts of the protein environment close to the chromophore on the isomerization barrier and on the chromophore structure.