Water drop

[Fabrício Bracht]

Hello. We have a student here in our lab that asked me for help with his simulations. He was assigned to study the hydrophobicity of cellulose. At first his work should be a simple one. He simulated a water droplet interacting with a cellulose surface through MD. After some time, the water droplet interacts with the surface and forms a half sphere(ish) on top of it. In order to get an idea of how hydrophobic the surface is, he needs to describe the format of the droplet. First he thought about doing it through image analysis, but that is when I thought bio3d could be useful. Is there a way to find the outermost water molecules of the droplet and use their position to fit some sort of curve in order to analyse its format? First I thought of defining the geometric center of the droplet. Then transpose it to the cellulose surface and use this point to calculate the distance of each water molecule. The molecules that have the highest distance would be chosen for further analyses. Well, this is just a thought experiment. I am not really sure as how I would do this in bio3d (R). So, some hints would be of great appreciation. I can provide files, in case you need. Fabrício