Cartesian reaction surface analysis of the CH2I2 ground state isomerization

We report the two-dimensional Cartesian reaction potential energy surface for the isomerization reaction of CH2I2 from diiodomethane to isodiiodomethane. In this surface the frame of the substrate CH2I is fixed and only the active iodine is allowed to move. The normal modes of the substrate atoms are analyzed and the reorganization energy is calculated. The results are compared with the minimum energy path for the isomerization on the fully relaxed potential surface.