Computational investigation of photo induced processes in alkyl nitrites and the product alkoxy radicals

The mechanistic aspects of the photo induced reactions of gaseous amyl nitrite have been investigated using ab initio calculations. We show that the C₅H₁₁O-NO bond dissociation mechanism is different on the S₁ and S₂ surfaces, respectively. The subsequent conformational changes in the ground state 1-pentoxy radical involves several barriers. Interestingly, we show that the intramolecular 1,5-H transfer in the 1-pentoxy radical proceeds in the opposite direction on the S₁ state compared to the S₀ reaction. Moreover, the results show that the excited state reaction of the alkoxy radical may be a proton transfer that proceeds on a repulsive surface.