Quantum Mechanical Studies on the Mode of Hydrogen Bonding, Stability and Molecular Conformations of Phenol-Water Complexes

It is experimentally well established that the phenolic systems such as phenol and diphenols undergo strong hydrogen bonding interaction with water molecule. But, the possible mode hydrogen bonding in phenol-water systems may be of different types. Although, the experimental methods are not always well enough to give the proper hydrogen bonding conformations in the phenol-water complexes. The hydrogen bonding ability in phenol-water systems can directly be influenced by changing the interacting sites in the given molecular systems, which could be investigated by theoretical studies. Generally, in phenol-water system, the hydrogen bonding is taking place through −OH group of phenol with water molecule, and this kind of interactions between phenol-water and diphenol-water complexes have been extensively investigated in electronic ground state by Quantum Mechanical MP4 calculations. It is also very important to study the stability of different phenol-water complexes and to find out the proper phenol-water complexes with minimized interaction energy. This study will also be helpful for understanding the effect of hydrogen bonding interaction in a better way on other aromatic systems.