[lammps-users] Fix heat command

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1

Steve,

I am trying to findout how much the velocities have been modified by adding heat. Below are the few lines of the prog. In the region cold, i tried to remove some heat and i use dump command to output vel’s before and after the timestep in two different files. But both files shows the same velocities. Shouldn’t it be different.

fix 4 all nve
dump 1 cold custom 1 velbefore.txt vx vy vz
fix 7 cold heat 1 -1.0
dump 3 cold custom 1 velafter.txt vx vy vz

Thanks
Ajit

2

When a dump file is written during a timestep has nothing to do
with where you place the command in an input script, relative to
fix commands (or other commands for that matter).

As its doc page explains, fix heat does store a scalar which can
be used to compute the total amount of heat added/subtracted
to the system. I suggest you use that to get the quantity you
want.

Steve