Potential for Water Clusters Modeling

Abstract

Distilled water, with the exception of a small natural ionization, consists of H₂O molecules. There is no reason to believe that these molecules, with the exception of small mutual deformations, differ from the H₂O molecules in a pair. This is confirmed by the Raman spectra and infrared absorption of water obtained by the works of Rahman and Stillinger. A computer simulation of a cluster of 55 molecules is performed. The representation of electric potential in both the five-center and four-center models implicitly implies the presence of non-electrostatic forces in the molecule. In the absence of such forces, according to the well-known Irnshaw theorem, it would be impossible to have stable molecules. We consider the pressure of supersaturated steam with a change in temperature, based on molecular rotation, only if we assume that the overwhelming number of water molecules has a free orientation without the influence of an external electric field. Molecular clusters, which we will study, are formed by molecules in contact with each other, able to rotate around their center under the action of intermolecular electrostatic forces. To test the suitability of our potential for modeling, the binding energy of a molecule in water and the sticking coefficient of a vapor molecule falling on a water surface will be calculated. These two parameters are also found from the saturation curve as calibration values. Thus, we model virtual intermolecular interactions between water molecules.