Translationally and internally hot H2 molecules are produced from the 157 nm photodissociation of amorphous solid methanol at 90 K by two distinct mechanisms: exothermic recombination of two H-atom photoproducts bound to the surface and unimolecular molecular elimination of H2 from the photoexcited methanol. The vibrationally hot H2 (v=2-5) products are characterized by high translational and rotational temperatures. A third mechanism, the almost thermoneutral abstraction of a hydrogen atom from methanol parent molecule by the photolytically produced hydrogen atom, yields translationally and rotationally cold H2 (v=0 and 1) products. Comparison with the results of the vacuum ultraviolet photolysis of water ice is discussed. Production of translationally hot and cold hydrogen atoms is also confirmed.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry