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Femto/Picosecond Transient Absorption Study of Ring-Opening Dynamics in Perimidinespirocyclohexadienone Derivatives
Anatoly V Metelitsa1, Olivier Poizat2, Guy Buntinx2
1Institute of Physical and Organic Chemistry, Southern Federal University, Stachki Av., 194/2, Rostov on Don, 344090, Russia.
Abstract:
The ring-opening dynamics of perimidinespirocyclohexadienone derivatives has been studied by means of time-resolved spectroscopy in cyclohexane and acetonitrile solutions. It has been established that molecular isomerisation leading to the open isomer occurs against the background of the S1 -S0 internal conversion of the cyclic form. In addition, the features of the observed spectral changes in the cyclohexane made it possible to distinguish formation of the photoproduct in the T1 state and its relaxation via intersystem crossing to the singlet ground state. The corresponding assignments for transient absorption bands were performed on the basis of TD-DFT calculations.
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