A MOLECULAR-DYNAMICS STUDY OF N-HEXADECANE DROPLETS ON A HYDROPHOBIC SURFACE

Molecular dynamics calculations have been used to investigate the comp ortment of clusters of n-hexadecane molecules deposited as patches on a non-polar surface formed from a 'self-assembled' monolayer of long-c hain alkylthiols With C-16 hydrocarbon tails. At room temperature, in contrast to intuition--but in general agreement with experiment-hexade cane does not seem to wet such a surface but rather appears to prefer to form a droplet. The contact angle estimated from the average drople t shape is about 60-degrees, which is about 20% larger than the experi mental value Possible reasons for the discrepancy are discussed.