Topology of the complicated Jahn-Teller intersection in the cyclic trinitrogen cationWe characterized the ground and electronically excited states of cyclic N_{3}^{+} at the equilibrium D_{3h} geometry and along Jahn-Teller distortions. Potential energy surfaces of the cyclic N_{3}^{+} lowest electronic excited states. The lowest excited states are derived from excitations from the doubly degenerate HOMO to the doubly degenerate LUMO, which gives rise to two exactly and two nearly degenerate electronic states [1,2]. In each multiplicity, the potential energy surfaces (PES) of four singlet and four triplet states are close in energy in equilateral geometry and form a complicated network of conical intersection's seams. A similar pattern will occur in other molecules with doubly degenerate HOMO and LUMO, e.g., benzene and sym-triazine. Relevant molecular orbitals of cyclic N_{3}^{+}. Both HOMO and LUMO are doubly degenerate. Topological features of D_{3h} intersection seam for the PES scan along the fully symmetric stretch. Virtually every possible topological feature is present on the PESs along the D_{3h} distortion of this simple beautiful molecule: conical intersection (CI) seams, triple conical intersections, intersection of D_{3h} CI with three C_{2v} CIs, glancing (Renner-Teller) intersection of the potential energy surfaces. Cyclic N_{3}^{+} can be considered a "molecule with the smallest Jahn-Teller effect". Scans of increased resolution along Jahn-Teller distortions (bending normal mode) of the four lowest triplet excited states' PESs. The Jahn-Teller linear term is extremely small which makes the intersection appear glancing rather than conical. Cyclic N_{3} is being investigated both experimentally [see P.C.Samartzis, J.J.M.Lin, et al. The simplest all-nitrogen ring: Photolytically filling the cyclic-N_{3} well . J. Chem. Phys. 126 (4): 041101 (2007)] and theoretically [see J.J.Dillon and D.R.Yarkony. Seams near Seams: The Jahn-Teller Effect in the 1E'' State of N_{3}^{+}. J. Chem. Phys. 126 (12): 124113 (2007)]. Related Publications51. 49. |