[gmx-users] Questions about GROMACS capabilities

[Eric Smoll]

Hello GROMACS users,

I have a few questions about what is possible in GROMACS:

1.) Is it possible "reset" the velocity of a subset of molecules in a MD
simulation to an arbitrary, non-thermal distribution? I am particularly
interested in the situation where all molecules of a certain type are reset
to a fixed COM speed in a fixed direction.

2.) If it is possible to "reset" the velocity of particles in a MD
simulation, is it possible to do so with a spatial trigger (e.g., all
molecules that reach the top of the unit cell have their velocity reset to
a specific speed and direction)?

3.) Is it possible to make a gas-liquid system where there are gas-liquid
interactions but no gas-gas interactions?

Best,
Eric