Characterization of triplet states of axially symmetric benzenes using the zeeman effect
Abstract
By means of low temperature spectroscopy of single crystals of sym-trichlorobenzene (TCB) and sym-tribromobenzene (TBB) we have determined that the principal Herzberg-Teller origins in the S_0 → T_1 transition correspond to out-of-plane vibrations. The assigned active modes for TCB are: 205 cm^(−1) (e"), 144 cm^(−1) (a"2) from phosphorescence; 119 cm^(−1) (e" or a"2) from absorption. For TBB the assigned modes are: 203 cm^(−1) (e") from phosphorescence; 166, 207 cm^(−1) (e" or a"2) from absorption. The singlet-triplet transitions are dominated by these vibronic origins, and the electronic origins are relatively weak and manifest crystal field induced interactions as evidenced by the Zeeman effect analysis. The appearance of these low frequency out-of-plane modes indicates that the halogen atom motion induced mixing of the pi and sigma type electronic states is dominating the transition mechanism.
Additional Information
© 1971 Elsevier B.V. Received 14 June 1971. This research was supported in part by a U.S. Department of Health Grant, GM 12592, and in part by the Advanced Research Projects Agency. We are indebted to the National Magnet Laboratory, M.I.T. for the use of their facilities in 1966 for the Zeeman work on TBB.Additional details
- Eprint ID
- 70665
- DOI
- 10.1016/0009-2614(71)80332-9
- Resolver ID
- CaltechAUTHORS:20160929-124949627
- NIH
- GM 12592
- Advanced Research Projects Agency (ARPA)
- Created
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2016-09-30Created from EPrint's datestamp field
- Updated
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2021-11-11Created from EPrint's last_modified field