Department of Physical Chemistry, Federal University of Rio de Janeiro, Cidade Universitária, Rio de Janeiro, 21941-909, RJ, Brazil.
Department of Physics, Federal University of Juiz de Fora, Campus Universitário, Juiz de Fora, 36015-260, MG, Brazil.
J Mol Model. 2023 May 30;29(6):189. doi: 10.1007/s00894-023-05514-7.
The rationalization of acid rain formation steps is fundamental for mitigating its effects. It is believed the hydroxysulfinyl radical is an intermediate species for the production of atmospheric sulfuric acid. Two stable configurations HOSO and HSO have been reported for such a radical in the gas phase. This work aims at studying these isomers in the aqueous medium. The electrical and reactivity quantities - electronic chemical potential ([Formula: see text]), chemical hardness ([Formula: see text]), and electrophilicity ([Formula: see text]) - are here calculated and compared. Considering first solvation shells (15 HO for HSO and 23 HO for HOSO), an increase of 25% in the dipole moment of HSO was obtained, while the dipole moment of HOSO decreases in 11%. Both solvated isomers grow softer ([Formula: see text] decreases) contrasted to the gas phase.
HOSO and HSO are studied through a sequential Monte Carlo/quantum mechanics approach. Lennard-Jones plus the Coulomb potentials were used to represent intermolecular potential interaction in the frame of the DICE package. Molecular structure calculations were performed at CASPT2/aug - cc - pV(T + d)Z level of theory using the MOLPRO suite of programs.
酸雨中各形成步骤的合理化对于缓解其影响至关重要。人们相信羟亚磺酰基自由基是大气中硫酸生成的中间物种。在气相中已经报道了这种自由基的两种稳定构型 HOSO 和 HSO。本工作旨在研究水溶液中的这些异构体。本文计算并比较了电和反应性参数——电子化学势([Formula: see text])、化学硬度([Formula: see text])和亲电性([Formula: see text])。考虑到第一溶剂化壳层（HSO 为 15 HO，HOSO 为 23 HO），HSO 的偶极矩增加了 25%，而 HOSO 的偶极矩减少了 11%。与气相相比，两种溶剂化异构体都变得更软([Formula: see text]减小)。
通过顺序蒙特卡罗/量子力学方法研究 HOSO 和 HSO。在 DICE 包中，使用 Lennard-Jones 加库仑势来表示分子间的相互作用势。在 CASPT2/aug - cc - pV(T + d)Z 理论水平上，使用 MOLPRO 程序套件进行分子结构计算。
