Internal conversion funnel in benzene and pyrazine: adiabatic and diabatic representation

✍ Scribed by W. Domcke; A.L. Sobolewski; C. Woywod

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 715 KB
• Volume: 203
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(93)85391-z

✦ Synopsis

The two lowest singlet surfaces of benzene and pyrazine exhibit a low-lying conical intersection on the reaction path to a biradical form called prefulvene. The potential-energy surfaces have been calculated with the complete-active-space self-consistentfield method. The conical intersection has been mapped out in two dimensions, the reaction coordinate to prefulvene and the coordinate of maximal interstate coupling. Quasi-diabatic polenlial-energy surfaces have been obtained via a block-diagonalization of the CI matrix. The ab initio diabatic potentials reveal that the conical intersection is locally well described by a simple linear model in both benzene and pyrazine.