ChemInform Abstract: Theoretical Investigation of Selenite(IV) and Hydrogenselenite(IV) Structures. Comparison with Sulfites and Tellurites

Abstract

003ChemInform Abstract (RHF-SCF calculations for SeO2, SeO32-, HSeO3-, and SeO2OH-using the frozen-orbital ECP method).

A Theoretical Study on the Reactions of Hg with Halogens: Atmospheric Implications

“…At the same time, a number of theoretical studies report both the geometries and vibrational frequencies of HgX and HgX2 species calculated at different levels of theory. [30][31][32][33][34][35][36][37][38] Table 1 shows, where experimental data exist, that in our calculations B3LYP with small LanL2DZ basis set for mercury and halogens overestimated the bond lengths by 0.1 to 0.2 Å and underestimated the vibrational frequencies by 40 to 100 cm -1 . Employing larger basis sets, ECP60MWB-(9s9p6d4f) for mercury and aug-cc-pVQZ for halogens, resulted in significantly more accurate bond lengths.…”

“…In the case of the diatomic radicals HgX, represented by the nondegenerate X 2 Σ state, the SO effect is zero; 41 the SO effect is also zero for HgX2 molecules because they are closed shell systems. Results of previous theoretical calculations 31,32,[36][37][38] are also presented in Table 2 for comparison purposes. These calculations have been performed at different levels of theory ranging from DFT to high-level correlated ab initio, however, in most cases moderate basis sets were employed that led to very high deviation of calculated energies from experiment.…”