Structure, thermodynamics, and dynamics of the liquid/vapor interface of water/dimethylsulfoxide mixtures

Molecular dynamics computer simulations are used to study the structure, th ermodynamics and dynamics of the liquid/vapor interface of water/DMSO (dime thylsulfoxide) mixtures. Both the infinite dilution limit (single DMSO mole cule) and four different finite concentration mixtures are investigated. Co nsidered are the potential of mean force for the adsorption of DMSO and the dependence of several surface structural properties (orientation, hydrogen bonding) and surface potential on the bulk concentration of DMSO. The adso rption dynamics are also investigated and compared with a diffusion model. In general, the results are in good agreement with recent experimental meas urements. (C) 1999 American Institute of Physics. [S0021-9606(99)50116-5].