Computational studies of CO2 activation via photochemical reactions with reduced sulfur compounds.

ABSTRACT: Reactions between CO(2) and reduced sulfur compounds (RSC), H(2)S and CH(3)SH, were investigated using ground and excited state density functional theory (DFT) and coupled cluster (CC) methods to explore possible RSC oxidation mechanisms and CO(2) activation mechanisms in the atmospheric environment. Ground electronic state calculations at the CR-CC(2,3)/6-311+G(2df,2p)//CAM-B3LYP/6-311+G(2df,2p) level show proton transfer as a limiting step in the reduction of CO(2) with activation energies of 49.64 and 47.70 kcal/mol, respectively, for H(2)S and CH(3)SH. On the first excited state surface, CR-EOMCC(2,3)/6-311+G(2df,2p)//CAM-B3LYP/6-311+G(2df,2p) calculations reveal that energies of <250 nm are needed to form H(2)S-CO(2) and CH(3)SH-CO(2) complexes allowing facile hydrogen atom transfer.

SUBMITTER: Baltrusaitis J 

PROVIDER: S-EPMC3461351 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature