Electronic structure, stability, and cooperativity of chalcogen bonding in sulfur dioxide and hydrated sulfur dioxide clusters: a DFT study and wave functional analysis

• Published in: Structural chemistry 2022-02, Vol.33 (1), p.179-193
• Main Author: Venkataramanan, Natarajan Sathiyamoorthy
• Format: Article
• Language: English
• Subjects: Air pollution; Analysis; Bonding strength; Chalcogen bonds; Chemistry; Chemistry and Materials Science; Clusters; Computer Applications in Chemistry; Density distribution; Density functional theory; Density functionals; Electron density; Electronic structure; Functional analysis; Hydrogen; Hydrogen bonding; Hydrogen bonds; Isomers; Original Research; Patches (structures); Physical Chemistry; Specific gravity; Structural stability; Sulfur; Sulfur dioxide; Theoretical and Computational Chemistry
• ISSN: 1040-0400; 1572-9001
• DOI: 10.1007/s11224-021-01827-6

Density functional theory calculations and wave functional analysis are used to examine the (SO 2 )n and (SO 2 )n–H 2 O clusters with n  = 1–7. The nature of interactions is explored by molecular electrostatic potentials, electron density distribution, atoms in molecules, noncovalent interaction, and energy decomposition analysis. The putative global minimum of SO 2 molecules has a 3D growth pattern with tetrahedral. In the hydrated SO 2 clusters, the pure hydrogen bond isomers are less stable than the O–S chalcogen bond isomers. The cluster absorption energy of SO 2 on water increases with the size of sulfur dioxide, implying reactivity of sulfur dioxide with water increases with size. The presence of cooperativity was evident from the excellent linearity plot of binding energy/polarizability vs the number of SO 2 molecules. Molecular electrostatic potential analysis elucidates the reason for the facile formation of S–O chalcogen than hydrogen bonding in hydrated sulfur dioxide. Atoms in molecule analysis characterize the bonds chalcogen and H bonds to be weak and electrostatic dominant. EDA analysis shows electrostatic interaction is dominated in complexes with more intermolecular chalcogen bonding and orbital interaction for systems with intermolecular H-bonding. The reduced density gradient (RDG) analysis of sulfur dioxide clusters has blue patches and green patches due to S–O chalcogen bonding O–O electrostatic interaction. The RDG analysis of hydrated sulfur dioxide clusters shows intensive blue patches and green patches for the existence of S–O chalcogen and hydrogen bonding respectively. Thus, the presence of strong electrostatic S–O chalcogen interaction and weak H bonds acts cooperatively and stabilize the hydrated sulfur dioxide clusters.