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arXiv · 1204.2142

Is photoisomerization of stilbene in solution directly promoted by solvent collisions?

S. A. Kovalenko·A. L. Dobryakov·N. P. Ernsting
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Abstract

Gas phase thermal isomerization rates of trans-stilbene at 300 K obey the Arrhenius law. In solution the rates increase ten-fold and depend only very weakly on excitation wavelength or intramolecular temperature. Both observations are difficult to reconcile within RRKM theory. Previously discussed mechanisms, like restricted IVR, nonadiabaticity, solvent-dependent barriers, or excitation-induced cooling, may explain the increase of the rates in solution but not their dependence on the excitation wavelength. The latter suggests that solvent collisions can directly promote the isomerization.

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S. A. Kovalenko, A. L. Dobryakov, N. P. Ernsting. 2012-12-05. Is photoisomerization of stilbene in solution directly promoted by solvent collisions?. https://arxiv.org/abs/1204.2142

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