Document Type : Regular Article
Department of Applied Sciences, Gauhati University, Guwahati-781014, Assam, India
Department of Applied Sciences, Gauhati University, Guwahati -781014, Assam, India
Molecular interaction occurs in organic solvent and water is a common phenomenon; but there observes a significant changes in physicochemical properties of organic solvent (OS)-water system, which may also affect the stability of such complexes. It has been clearly observed the optimized models of OS-water complexes show strong hydrogen bond formation and there occurs a change in bond distances and angles during molecular interaction with water molecule or H3O+. Organic solvents such as aldehyde, ketone, carboxylic acid, amine, aniline, amide etc. might have different interaction modes with water molecule, whereas the proton donor-acceptor nature of such system greatly impacts on the change in free energy, enthalpy, zero-point energy etc. The hydrophobic or hydrophilic nature of such a system controls the stability of donor-acceptor complex which also changes their acid-base behaviour. Analysis of optimized models also show the detailed change in geometry of organic solvent (OS)-water molecular complexes. The minute details of free energy change (∆Gº), enthalpy change (∆Hº), zero-point energy change(∆ZPE), change in electron charge density, effect of protonation etc. of OS-H2O/H3O+ complexes have been studied by quantum mechanical calculation.