Fig. 3: Adiabatic potential energy surface (APES) of the kk-VV0 excited state 3E.
From: Theory of the divacancy in 4H-SiC: impact of Jahn-Teller effect on optical properties
a APES of the lower branch of the 3E state, which takes a “tricorn sombrero” shape with three minima and three saddle points. Qx, Qy configuration coordinates represent the collective motion of effective e-symmetry modes. EJT is the JT stabilization energy, which is the difference in energy between the high-symmetry and distorted configurations. The three minima are separated by three barriers with the energy of δJT. b Contour plot of the APES. c Computed potential energy curve along the path defined in (b). The potential energy curve is fitted by Eq. (1) (see text).
