Greetings,
I know that there are a bunch of different MD techniques to calculate the melting point of a component. However, I want to calculate the boiling point of methane at a particular pressure. is there any known MD technique to do so? One thing that comes to my mind is to do NPT simulations at different temperatures and monitor the mass density. The boiling temperature would be the temperature where the transition in the fluid’s density occurs. Any suggestions?
The problem is that, generally, the fluctuations in nanoscale systems are too small to simply sample phase transitions. For example, if you simply sit (for example) a nanobox of water at 373K and 1 bar, the system will only very rarely “jump” from liquid to gas.
This is why (as you say yourself) there are a bunch of different MD techniques to calculate the melting point of a substance, none of which are “scan NPT simulations in T and find the phase jump”. It’s similar for the boiling point. Google (Scholar) is your friend.