Various ab initio computations, as, e.g., in G. J. Halász and Á. Vibók, Int. J. Quantum Chem. 111, 342 (2011), have shown that in molecules of the type (HCCH)+, when the extremal H atoms are distorted from a linear form but maintain a planar geometry, a pair of conical intersections (ci) occur at such positions that the ratios of the distortional coordinates of the two atoms are in the two cis reciprocals of each other. These computations have here been extended to locate the cis also for HCNH. The two groups of results are explained by simple analytic perturbational expressions for the energy differences of the lowest adjacent electronic states, with inclusion of excited state effects.
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry