Molecular dynamics simulation of methanol clusters

摘要

Methanol clusters have been studied based on Molecular Dynamics simulations. The methanols are described using the three-site OPLS potential model by Jorgensen. Five separate clusters with sizes up to 512 molecules are treated at two different temperatures, 200 K and 300 K, respectively. Several properties, for example, the local density, electric potential and the normal pressure, are calculated. Also, the surface potential of methanol is computed, based on the radial profiles of the electric potential. It is shown, once again, that the quadrupolar contribution to the surface potential is important to the total value of the surface potential. Using the size dependence of the work of cluster formation, it is found that the surface tension of methanol decreases monotonously upon decreasing the radius of the dividing surface approaching a limiting value. The calculated limiting value for surface tension agrees well with that, observed experimentally for the plane surface of methanol. (C) 1998 American Institute of Physics. [S0021-9606(98)01745-0]. [References: 32]