Jahn-Teller effect and possible superconductivity in [18]annulene

Abstract

Abstract We discuss the Jahn-Teller effect and possible superconductivity in negatively charged [18]annulene, (CH) 18 , which has a highly symmetric D 6h geometry in the neutral state. Electron-phonon coupling constants in model one-dimensional crystals of (CH) 18 − and (CH) 18 3− are calculated and analyzed using the density functional B3LYP method. The lowest two frequency modes (116 cm −1 and 405 cm −1 ) causing distortions of the C-C framework of [18]annulene and the highest frequency mode (3201 cm −1 ) of C-H stretching appear to give significant electron-phonon coupling constants. Possible preconditions under which idealized one-dimensional crystals of (CH) 18 − and (CH) 18 3− can exhibit superconductivity at finite temperature are considered.