Dear all,
I am trying to use ‘fix heat’ to conduct NEMD simulation, which add and reduce energy from two regions for every n time steps. And I used the new version of fix heat which contains ‘region’ option. While I got this error ’ Could not find fix group ID’. This error came after the fix heat command. The following is the input files.
Thanks.
MD simulation of Ar thermal conductivity
Initialization
units lj
dimension 3
newton on
boundary p p p
atom_style atomic
neighbor 0.3 bin
neigh_modify check yes
lattice fcc 0.844
region box block -4 4 -4 4 -4 4 units lattice
create_box 1 box
create_atoms 1 box
region up1 block INF INF INF INF -0.5 -0.25 units lattice
region up2 block INF INF INF INF 0.5 0.75 units lattice
region up union 2 up1 up2
region down1 block INF INF INF INF -3.5 -3.25 units lattice
region down2 block INF INF INF INF 3.5 3.75 units lattice
region down union 2 down1 down2
region hot block INF INF INF INF 0.0 0.25 units lattice
group hot region hot
region cold block INF INF INF INF -4.0 -3.75 units lattice
group cold region cold
mass 1 1.0
#mass0 6.633e-26
#epsilon0 1.67e-21
#sigma0 3.405e-10
velocity all create 0.71 458127641 mom yes rot yes dist gaussian units box
Tersoff potential *********************************************************
pair_style lj/cut 2.8
pair_coeff 1 1 1.0 1.0 # LJ parameters for Ar-Ar
fix temp all temp/berendsen 0.71 0.71 0.0466
fix nve all nve
compute ke all ke/atom
variable temp atom c_ke/(1.5*1.0)
fix temp_profile all ave/spatial 1 100000 100000 z lower 0.25 v_temp file temp.profile units lattice
compute up_temp all temp/region up
compute down_temp all temp/region down
variable delta_temp equal c_up_temp-c_down_temp
fix delta_out all ave/time 1 100000 100000 v_delta_temp file delta_temp.dat
thermo_style custom step temp etotal vol
thermo_modify lost warn
thermo 1000
Run
timestep 0.000466
run 100001
unfix temp
fix hot qin heat 1 1.0 region hot
fix cold qout heat 1 -1.0 region cold
variable thermal_conductivity equal 50.00.51.67e-21/3.405e-10/sqrt(6.633e-26/1.67e-21)/((4.08.08.08.0/0.844)^(1.0/3.0)3.405e-102.0f_delta_out*1.67e-21/1.3806504e-23)*6.0/8.0
fix thermal_conductivity_out all ave/time 100000 1 100000 v_thermal_conductivity file thermal_conductivity.dat
Run
run 1000000