Desorption of hydroxyl radicals in the vacuum ultraviolet photolysis of amorphous solid water at 90 K

作者：Hama Tetsuya; Yabushita Akihiro; Yokoyama Masaaki; Kawasaki Masahiro^*; Andersson Stefan

来源：Journal of Chemical Physics, 2009, 131(5): 054508.

DOI：10.1063/1.3191731

• free radicals
• ice
• multiphoton processes
• oxygen compounds
• photodissociation
• photoionisation
• photon stimulated desorption
• reaction kinetics
• surface chemistry
• water

We have studied the desorption dynamics of OH radicals from the 157 nm photodissociation of amorphous solid water (ASW) as well as H(2)O(2) deposited on an ASW surface at 90 K. The translational and internal energy distributions of OH were measured using resonance-enhanced multiphoton ionization methods. These distributions are compared to reported molecular dynamics calculations for the condensed phase photodissociation of water ice and also reported results for the gas phase photodissociation of H(2)O at 157 nm. We have confirmed that OH radicals are produced from two different mechanisms: one from primary photolysis of surface H(2)O of ASW, and the other being secondary photolysis of H(2)O(2) photoproducts on the ASW surface after prolonged irradiation at 157 nm.

• 出版日期2009-8-7