Article pubs.acs.org/JPCA
Computational Studies of CO2 Activation via Photochemical Reactions with Reduced Sulfur Compounds Jonas Baltrusaitis,*,†,# Eric V. Patterson,‡ and Courtney Hatch§ †
Departments of Chemistry and Chemical/Biochemical Engineering, University of Iowa, Iowa City, Iowa 52242, United States Department of Chemistry, Truman State University, Kirksville, Missouri 63501, United States § Department of Chemistry, Hendrix College, Conway, Arkansas 72032, United States ‡
S Supporting Information *
ABSTRACT: Reactions between CO2 and reduced sulfur compounds (RSC), H2S and CH3SH, were investigated using ground and excited state density functional theory (DFT) and coupled cluster (CC) methods to explore possible RSC oxidation mechanisms and CO2 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 CO2 with activation energies of 49.64 and 47.70 kcal/mol, respectively, for H2S and CH3SH. On the first excited state surface, CREOMCC(2,3)/6-311+G(2df,2p)//CAM-B3LYP/6-311+G(2df,2p) calculations reveal that energies of
