Ab initio studies of negative ion‐molecule(s) clusters present in the atmosphere. II. OH⁻(H₂O)_n for n = 0, 2, 3, 4

Abstract

Ab initio calculations are performed with 6–31G basis set to study the geometry and binding of the H3O 2−, H5O 3−, H7O 4−, and H9O 5− complexes. The H3O 2− complex is also investigated with the 6–31 G* basis set and MP2 (Moller–Plesset perturbation theory of second order).

Structures, energetics, and spectra of OH−(H2O)n and SH−(H2O)n clusters, n=1–5: Ab initio study

“…[2][3][4][5][6] Recently, infrared ͑IR͒ spectroscopic measurements of OH Ϫ (H 2 O) n produced by a supersonic expansion have been carried out. 7 Although a number of theoretical studies for OH Ϫ (H 2 O) n (nϹ3) are available, [6][7][8][9][10][11][12][13][14][15][16] only a few studies for OH Ϫ (H 2 O) n (nϭ4,5) are available. 7,14 - 16 We studied OH Ϫ (H 2 O) n (nϹ5) at the MP2/aug-cc-pVDZ and MP4/aug-cc-pVDZ//MP2/aug-cc-pVDZ levels.…”

“…1 OH Ϫ is of particular interest in hydration because of its involvement in acid-base chemistry. For OH Ϫ (H 2 O) n in the gas phase, many experimental 2-7 and theoretical studies [8][9][10][11][12][13][14][15][16] have been performed. Further, for OH Ϫ in aqueous solution, Monte Carlo calculations 17,18 and ab initio molecular dynamics studies [19][20][21][22] have been carried out.…”

Structure of the First Solvation Shell of the Hydroxide Anion. A Model Study Using OH-(H2O)n (n = 4, 5, 6, 7, 11, 17) Clusters

“…Although most computations done up to now have focused their attention in the n ≤ 3 OH - (H 2 O) n clusters, there are also some studies on larger clusters. Many computations − have been aimed at finding the most stable structure of the OH - (H 2 O) 3 clusters, as it defines the solvation number of the OH - anion, and reproducing the shell effect after n = 3 in the incremental association enthalpy. These studies indicate that the first solvation shell of the OH - anion is constituted by three water molecules.…”

Dissociative photodetachment studies of O−(H2O)2, OH−(H2O)2, and the deuterated isotopomers: Energetics and three-body dissociation dynamics

“…16,20,21,23,30,31 Complementing these experiments are a number of theoretical studies of the structure and energetics of OH Ϫ ͑H 2 O) n . [32][33][34][35][36][37][38][39] Efforts have also been made to provide a link between small cluster data and bulk aqueous solvation. 15,40,41 The most likely structure of OH Ϫ ͑H 2 O) 2 has a central OH Ϫ solvated to two waters via hydrogen bonds in a bent, almost planar configuration 34 as shown in Fig.…”

“…15,34,36,38,41 As with O Ϫ , ⌬H 298 K,1←2 hyd ͑OH Ϫ ) is smaller than ⌬H 298 K,0←1 hyd ͑OH Ϫ ), with the most recent experimental values of the latter quantity centered around 1.16 eV. 13,19,[32][33][34]36,[41][42][43][44][45] For this cluster, the only low energy dissociative photodetachment pathway is…”