(235b) Exploring The Properties And Vapor Processing Of Organic Coated Water Droplets Using Molecular Dynamics Simulation

Atmospheric aerosols play a very important role in atmospheric processes and have a major influence on the global climate. In this paper, we report results of a Molecular Dynamics study on the unique properties of organic coated water droplets. In particular we find that for particles preferring an inverted micelle structure, the lower chain-chain interaction, with increasing radial distance from the water-organic interface, results in a negative internal radial pressure profile for the organic layer. As a result, a coated particle behaves as though the surface tension is ?negative?, and implies that such a particle will inherently have an inverse Kelvin vapour pressure effect, resulting in increased water condensation.

We have also measured the uptake rate as a function of water droplet cluster size and averaged these results over the Boltzmann velocity distribution to generate sticking coefficients. In general we observe that these materials are quite effective at processing water vapor.