The CO2-O2 van der Waals complex

Publication date: 15 August 2017 Source:Computational and Theoretical Chemistry, Volume 1114 Author(s): Friedrich Grein Using the explicitly correlated CCSD(T)-F12 method with cc-pVXZ-F12 (VXZ-F12) and aug-cc-pVXZ (AVXZ) (up to X=Q) basis sets, various structures of the triplet CO2-O2 complex were investigated. Accordingly, the planar slipped-tilted isomer is most stable, with a binding energy (ΔE) of 230cm−1, followed by the cross-shaped C2v-X isomer, having ΔE=202cm−1 and by the in-plane T-shaped C2v-Ta isomer with ΔE=181cm−1 (energies obtained from counterpoise corrected optimizations using the VQZ-F12 basis set). Binding energies using the AVQZ basis set are similar, with 238, 211 and 188cm−1, respectively. Frequency calculations showed that C2v-Ta is a first-order saddle point. The binding energies are in line with values obtained for related CO2 complexes, although the slipped-tilted structure of the most stable isomer of the CO2-O2 complex is somewhat unexpected. To our knowledge, this is the first theoretical study of CO2-O2 complexes. Graphical abstract

Source: Computational and Theoretical Chemistry - May 27, 2017 Category: Chemistry Source Type: research