Catalytic effect of (H2O)n (n=1-2) on the hydrogen abstraction reaction of H2O2 + HS → H2S + HO2 under tropospheric conditions

The effects of (H2O)(n) (n = 1-2) on hydrogen abstraction reaction (H2O2 + HS -> H2S + HO2) have been investigated at the level of theories of B3LYP and CCSD(T). The aug-cc-pVTZ basis set has been used in the present treatment. The catalytic effect has been found to be small for water dimer and is significant for water, because the effective rate constant for the water -catalyzed reaction being 3-4 orders of magnitude larger than the corresponding water-dimer assisted reaction. Compared to the un-catalyzed reaction, the rate enhancement due to water catalysis at lower temperature (e.g., 240 K) was only 0.17%, which was increased to 72.7% at higher temperature (e.g., 325 K). (C) 2017 Elsevier B.V. All rights reserved.