Density functional theory study of the multimode Jahn–Teller problem in the open-shell corannulenes and coronenes

• Published in: Chemical physics Vol. 460; pp. 64 - 74
• Main Authors: Andjelković, Ljubica, Gruden-Pavlović, Maja, Zlatar, Matija
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 16-10-2015
• Subjects: Corannulene ions; Coronene ions; Intrinsic Distortion Path; Jahn–Teller distortion; Multimode problem; Jahn–Teller distortion; Multimode problem; Corannulene ions; Coronene ions; Intrinsic Distortion Path
• ISSN: 0301-0104
• DOI: 10.1016/j.chemphys.2015.05.007

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•Analysis of the multimode JT effect in corannulene and coronene ions is presented.•Multideterminantal-DFT quantifies the JT distortion in fast and efficient way.•Chemical mechanism of the distortion is derived by Intrinsic Distortion Path model.•The CC stretching modes afford the largest vibronic coupling constants.•The softest modes are responsible for the relaxation of the molecules.
Analysis of the multimode Jahn–Teller (JT) distortion in anions and cations of corannulene and coronene is presented, combining multideterminantal-DFT (MD-DFT) and Intrinsic Distortion Path (IDP) methods. The JT distortion is derived from the sum of contributions of all possible JT active normal modes. The CC stretching modes play the most important role in the stabilization of the systems, in all investigated species, pushing the nuclei toward the minima on the potential energy surface. The further inspection of the IDP revealed that the relaxation of the geometry arrives in the final part of the path and is encountered by the softest vibrational modes. The same trend was observed in cyclopentadienyl radical, benzene anion, benzene cation and fullerene ions. This gives microscopic origin into the mechanism of the distortion and provides general behavior of the JT effect in these similar molecules. Moreover, MD-DFT and IDP, as fast and fully non-empirical approaches, can be considered as a reliable tool for better understanding of the JT effect.