Evaluation of the crystalline tetracene triplet davydov splitting

✍ Scribed by A. Tiberghien; G. Delacote

• Publisher: Elsevier Science
• Year: 1971
• Tongue: English
• Weight: 290 KB
• Volume: 8
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(71)80584-5

✦ Synopsis

The magnitude and sign of the first excited triplet state Davydov splitting of the tetracene single crystaI has been calculated. It is found that the charge transfer contribution is dominant over the exchange integral and of opposite sign. Assuming a Frknck-Condon factor of 0.20 for the O-O transition, one gets E_-X+=30 cm-l_ It is also shown that the f-) state should be b polarized and the (+) state a polarized. . l-I~TRODUCTTON The Davydov splitting of the first excited triplet .&ate has already been measured in different neat molecuiar crystals like anthracene [l], naphthalene [2] and benzene f"]. It has still not been measured, to otxr knowledge, in a tetracene single crystal. One of the major reasons is the difficulty of.getting thick enough crystals to over-.come the very'iow oscillator strength of the forbidden singiet-triplet transijion. + Work supported by the D.G.R.S.T. under contract no 7002159. ** Laliornroire assdci6 au C.N.R.S.

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