MELTING OF THE WATER HEXAMER
E. D. Belega, D. N. Trubnikov, E. A. Cheremukhin
Moscow State University, Moscow, Russia
Keywords: кластеры молекул воды, плавление гексамера воды, индекс Линдемана, фазовые переходы в кластерах, изомеры кластеров воды, water molecule clusters, melting of the water hexamer, Lindemann index, phase transitions in clusters, water cluster isomers
Abstract
Results are presented for a molecular dynamics simulation of melting of the water hexamer from three-dimensional configurations (the
book,
cage, and
prism isomers). The interactions between water molecules are described using two rigid potentials-TIP4P and TIP5P. The isomer geometry is determined using the connectivity matrix of the H-bond network graph. It is found in a numerical experiment that the Lindemann index, which shows the fluctuations in the length of intermolecular bonds, behaves similarly for all the studied initial isomers of the cluster. The melting of the cluster is found to depend on the interaction potential used in the study. For the cluster’s full energy, regions are identified which can be attributed to the premelting phase, which is dominated by the
book isomer for TIP4P and
ring isomer for TIP5P. The energy region attributed to the quasi-liquid phase of the cluster is shown to be characterized by isomers with ring and linear structures for both of the potentials.
DOI: 10.1134/S0022476615010084
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