Melting of Water Molecule Clusters in a Strong Electric Field under the Conditions Modeling Arctic Stratosphere

The melting of (H₂O)₄₀ice microparticles under the conditions of subarctic stratosphere was numerically simulated using the Monte-Carlo method. The melting point of the microparticles was found to be 60 K lower than the melting temperature of bulk ice. The melting was detected by the behavior of the internal energy of microparticles, their heat capacity and electric susceptibility. The melting was accompanied by a qualitative change in the molecular orientation order in a cluster. Abrupt changes in the molecular arrangement in the cluster were not found. An electric field destroys the molecular orientation order in the cluster, and the clear-cut phase transition disappears. An electric field increases the rotational mobility of molecules.