Nonempirical investigation of the probability for radiationless transitions. I

The probability for radiationless T₁–S₀-transitions was investigated. An expression for the Franck-Condon factor is obtained by means of exact integration, on the basis of the theory of multiphonon transitions. This expression is utilized for the investigation of the radiation-less T₁–S₀-transition in the formaldehyde molecule. It is found that the transition mentioned does not play a large role.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii Fizika, No. 11, pp. 32–37, November, 1971.