Hydrocarboxyl Radical as a Product of α-Alanine Ultraviolet Photolysis.

UV photodissociation of α-alanine was studied by parahydrogen matrix isolation infrared spectroscopy. The temporal behavior of Fourier transform infrared spectra revealed that UV irradiation at 213 nm yielded the HOCO radical as a direct photoproduct from the S excited state. The concentration of HOCO quickly approached a steady state due to secondary photodissociation of HOCO to produce CO + H or CO + OH.

UV photochemistry of benzene and cyclohexadienyl radical in solid parahydrogen.

Matrix-isolation spectroscopy in solid parahydrogen is a powerful technique for the study of photochemical reactions in detail. It is especially suited for the detection of chemical intermediates and unstable molecular products of photochemical reactions that are otherwise difficult to observe using other conventional spectroscopic techniques. Here, we have revisited UV photochemistry of benzene induced by 193 and 253.