Ab initio quantum-chemical computations of the electronic states in HgBr2 and IBr: Molecules of interest on the Earth’s atmosphere
The electronic states of atmospheric relevant molecules IBr and HgBr are reported, within the UV-Vis spectrum range (170nm≤λphoton≤600 nm) by means of the complete-active-space self-consistent field/multi-state complete-active-space second-order perturbation theory/spin-orbit restricted-active-space state-interaction (CASSCF/MS-CASPT2/SO-RASSI) quantum-chemical approach and atomic-natural-orbital relativistic-correlation-consistent (ANO-RCC) basis sets. Several analyses of the methodology were carried out in order to reach converged results and therefore to establish a highly accurate level of theory. Good agreement is found with the experimental data with errors not higher than around 0.1 …
Ab initio quantum-chemical computations of the absorption cross sections of HgX2 and HgXY (X, y = Cl, Br, and I): Molecules of interest in the Earth's atmosphere
13 pags., 4 figs., 2 tabs.
Photoreduction of gaseous oxidized mercury changes global atmospheric mercury speciation, transport and deposition
9 pags, 8 figs. -- Correction autor: https://doi.org/10.1038/s41467-022-28455-w http://hdl.handle.net/10261/268181
Gas-Phase Photolysis of Hg(I) Radical Species: A New Atmospheric Mercury Reduction Process
The efficient gas-phase photoreduction of Hg(II) has recently been shown to change mercury cycling significantly in the atmosphere and its deposition to the Earth's surface. However, the photolysis of key Hg(I) species within that cycle is currently not considered. Here we present ultraviolet-visible absorption spectra and cross-sections of HgCl, HgBr, HgI, and HgOH radicals, computed by high-level quantum-chemical methods, and show for the first time that gas-phase Hg(I) photoreduction can occur at time scales that eventually would influence the mercury chemistry in the atmosphere. These results provide new fundamental understanding of the photobehavior of Hg(I) radicals and show that the …