Hello,
I was looking at the in.langevin example in the KAPPA folder and was wondering how you specify the region to apply the hot and cold areas when both fixes are for “all” atoms. Does calling the fix_modify reference the compute that then gives the region on which to act? If so, what is the benefit of doing this indirectly through a compute rather than just indicating the region in the langevin fix? Is it just more efficient?
Thanks,
Michael
heat layers
region hot block INF INF INF INF 0 1
region cold block INF INF INF INF 10 11
compute Thot all temp/region hot
compute Tcold all temp/region cold
1st equilibration run
fix 1 all nvt temp $t $t 0.5
thermo 100
run 1000
velocity all scale $t
unfix 1
2nd equilibration run
fix 1 all nve
fix hot all langevin {thi} {thi} 1.0 59804 tally yes
fix cold all langevin {tlo} {tlo} 1.0 287859 tally yes
fix_modify hot temp Thot
fix_modify cold temp Tcold
variable tdiff equal c_Thot-c_Tcold
thermo_style custom step temp c_Thot c_Tcold f_hot f_cold v_tdiff
thermo 1000
run 10000