A molecular dynamics study of n-hexadecane droplets on a hydrophobic surface

Abstract

Molecular dynamics calculations have been used to investigate the comportment of clusters of n-hexadecane molecules deposited as patches on a non-polar surface formed from a 'self-assembled' monolayer of long-chain alkylthiols with C16 hydrocarbon tails. At room temperature, in contrast to intuition-but in general agreement with experiment-hexadecane does not seem to wet such a surface but rather appears to prefer to form a droplet. The contact angle estimated from the average droplet shape is about 60 degrees , which is about 20% larger than the experimental value. Possible reasons for the discrepancy are discussed.