The effects of water microsolvation on the C2O4- ⇆ CO2•CO2- core switching reaction: Perspective from exploration of pathways on the potential energy surfaces of small [(CO2)2(H2O)n]- (n=1 and 2) clusters

Water microsolvation effects on the C2O4- <-> CO2.CO2- anion core switching reaction in the small [(CO2)(2)(H2O)(n)](-) (n = 1 and 2) clusters have been computationally studied. All low-energy rearrangement pathways have been explored using global reaction route mapping (GRRM) techniques. Both the C2O4- dimer anion core and CO2.CO2- monomer anion core have various hydration structures. The former is stable in [(CO2)(2)(H2O)(1)](-) while the latter becomes stable in [(CO2)(2)(H2O)(2)](-). It was found that the energy levels of the transition states significantly depend on the detailed hydration structures. We also performed Born-Oppenheimer molecular dynamics calculations to simulate photoelectron spectra of the [(CO2)(2)(H2O)(n)](-) clusters. (C) 2017 Elsevier B.V. All rights reserved.