We study thermochemical [1] and electronic properties [2] of halogen-containing species with relevance to several atmospherical processes (e.g. catalytic ozone destruction and air quality).
On the one hand, we found that Gn (Gaussian-n, n = 3,4) ab initio computations are accurate theoretical methods to provide reliable heat of formation and carbon-halogen bond-energy values of a wide variety of chlorinated and brominated organic species [1]. These data will be implemented in climate models in order to evaluate the atmospheric-impact of these compounds.

On the other hand, we have shown that the CASPT2 methodology ("Complete Active Self Consistent Field Perturbation Theory”) is also an excellent method for providing reliable values of absorption optical parameters (within the UV-Vis range) of representative species such as IBr and HgBr2 which have particular connotation in photochemical atmospheric processes [2].

[1] J.Z. Dávalos, R. Notario, C.A. Cuevas, J.M. Oliva, A. Saiz-Lopez: “Thermochemistry of halogen-containing organic compounds with influence on atmospheric chemistry”. Comp. Theor. Chem. 1099 (2017) 36-44. DOI:10.1016/j.comptc.2016.11.009
[2] S.P. Sitkiewicz, J.M. Oliva, J.Z. Dávalos, R. Notario, A. Saiz-Lopez, D.R. Alcoba, O.B. Oña, D. Roca-Sanjuán; “Ab initio quantum-chemical computations of the electronic states in HgBr2 and IBr: Molecules of interest on the Earth's atmosphere”. J. Chem. Phys. 145 (2016) 244304, 1-14. DOI:10.1063/1.4971856