Characterization of the conical intersection of the visual pigment rhodopsin at the CASPT2//CASSCF/AMBER level of theory
The branching plane associated with the conical intersection controlling the photochemical Z -> E isomerization reaction of rhodopsin has been mapped using a CASPT2//CASSCF/ AMBER quantum mechanics-molecular mechanics method. The nature of the derivative coupling and gradient difference vectors spanning the branching plane has been investigated, showing that the conical intersection is not only as