Photo-Transformation Trajectories of Nitro-Spiropyran in Hybrid Compounds with [60]Fullerene

다국어 초록 (Multilingual Abstract)

<P>Photo- and thermo- isomerization trajectories of various conversion pathways between nitro-spiropyran and its <I>trans</I>-<I>trans</I>-<I>cis</I> merocyanine form were produced and the role of <I>n</I>π* states was investigated along the corresponding potential energy surface calculated using the ωB97XD functional and the cc-pVDZ basis set. The nondissociative <I>n</I>π* states on the photoisomerization trajectories can switch from/to the dissociative photoactive ππ* state at two intersections between their energy surfaces. The photochromic properties inherited in hybrid compounds of nitro-spiropyran-containing [60]fullerene are interpreted due to a reversible “dual energy bypass” ππ*↔<I>n</I>π* mechanism in terms of both adiabatic absorption and highly effective nonadiabatic dissipative transitions between the excited states of the photochromic fragment, that prevents energy loss through the [60]fullerene and in this way keeps the photochromic properties intact.</P>
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