MOLECULAR-DYNAMICS STUDY OF 2-COMPONENT SYSTEMS - THE SHAPE AND SURFACE-STRUCTURE OF WATER ETHANOL DROPLETS/

Molecular dynamics simulations have been performed at T = 260 K on thr ee different sized ethanol/water droplets with a mole fraction of etha nol x = 12%. The calculations were initiated from near spherical confi gurations taken from simulations of the bulk mixture with the same com position. The results are discussed in comparison to the microphysical models used in nucleation theories. For the droplet having a comparab le size to the so-called ''critical'' cluster, all the ethanol molecul es repartition to the surface. The shapes and surface structure of the droplets have been characterized and exhibit increasing fluctuations with decreasing size. These two observations may help explain the pres ent discrepancy between the predicted and calculated rates of nucleati on for ethanol/water droplets.