Jahn-Teller-like progressions in the absence and presence of Jahn-Teller distortions

✍ Scribed by Benjamin Scharf

• Publisher: Elsevier Science
• Year: 1983
• Tongue: English
• Weight: 375 KB
• Volume: 96
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(83)80123-7

✦ Synopsis

Prominent progressions of non-toti3i& wmmctric modes majr ensue in non-iinear mokcules in electronic transitions in-% alvk~~ degenerate states in the absence of Jahn-Teller distortions. In the presence of Jabn-Tel.kr interzctions prominent non-Jahn-Teller progreesions may result Jahn-Teller distortions [I] may ensue in degenerate electronic states of non-linear moiecules [I--41]. Jahn-Teller distortions in nuclear equilibrium configuration arise via linear vibronic coupling involving non-totally wrnmetric modes which symmetry species is contained in the symmetric direct product of Ihe symmetry representatiott of the degenerate electronic state by itself-The existence of Jahn-Teller distortions is manifested in dectronic spectra by the appearance of O-O, O--I, O-Z_. vibronic progressions in the non-rotally symmetric linearly J&n-Teller active modes [l--37] _ Conversely appearance of such tibronic progressions in non-totally symmetric modes would be considered as strong evidence for the prevalence of Jahn-Teller distortions in at least one of the electronic states between which the radiative transition takes place.

In this Iettet we show that prominent vibronic progressions in modes capable of Jahn-Teller activity may ensue even in the absence of Jahn-Teller distartions. Furthermore, we also show that promkent vibronic progressions of non-totally symmetric modes which cannot be Jahn-Teller active may ensue when k&n-Teller activity prevails.