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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Femto /皮秒瞬态吸收研究Perimidinespirocyclohexadienone衍生物的开环动力学

通过在环己烷和乙腈溶液中的时间分辨光谱研究了perimidinespirocyclohexadienone衍生物的开环动力学。已经确定，导致环状异构体发生的分子异构化是在环状形式的S _1- S ₀内部转化的背景下发生的。另外，在环己烷中观察到的光谱变化的特征使得可以区分光产物在T ₁状态下的形成及其通过系统间相交到单重态基态的弛豫。瞬态吸收带的相应分配是根据TD-DFT计算进行的。