Modeling of interaction between a water molecule and crystal surfaces

An interaction model between a water molecule and magnesium oxide crystal surface is considered. The potential energy of the system is calculated with help the molecular mechanics method, that takes into account the atom-atom interaction using model semi-empirical potentials. Fragment of the crystal surface is represented by the cluster model, that consists of a finite number of atoms belonging to the surface and the nearest atomic planes. Different cluster models containing from 9 to 24 atoms of magnesium oxide were considered. It is shown that the distance between the water molecule and the surface in equilibrium point is 3 Å. It is found that the interaction is electrostatic in its nature. Stretching frequencies of the water molecule adsorbed at the surface are calculated. The results obtained are compared with the quantum-mechanical calculations. Bibliogr. 15. Il. 3. Table 1.