ave/spatial

Dear all,

I want to find thermal conductivity using keyword "thermal/conductivity" of a SiGe nanowire. I have one script that works in old lammps version.

But in new version "ave/spatial" keyword should be replaced by "fix ave/chunk" and "compute chunk/atom".

I change the line ** (see part of script below):

#------- Thermal conductivity calculation, switch to NVE ------#
variable dt equal 0.0005 # 0.5fs; in picoseconds = 0.5e-12 s
variable W equal 1000 # Swap atoms every this many steps
variable NRUN equal 20000000
variable time equal step*v_dt
variable nslab equal 20
variable slabw equal 1.0/v_nslab

timestep \{dt\} \#\#0\.0005 picosecond = 0\.5 femtosecond thermo {W}
fix NVE all nve
compute ke all ke/atom
variable temp atom c_ke/v_kB/1.5
** fix TEMPP all ave/spatial 1 100000 100000 z lower \{slabw\} v\_temp file tmp\.profile units reduced fix TKE all thermal/conductivity {W} z \{nslab\} swap 1 variable TKEN equal f\_TKE thermo\_style custom step temp pe etotal press pxx pyy pzz f\_TKE run {W}
variable SIflux equal v_TKEN/v_time/v_Area*v_convert
thermo_style custom step temp pe etotal press pxx pyy pzz f_TKE v_SIflux
thermo_modify flush yes
run ${NRUN}

Dear all,

I want to find thermal conductivity using keyword "thermal/conductivity"
of a SiGe nanowire. I have one script that works in old lammps version.

But in new version "ave/spatial" keyword should be replaced by "fix
ave/chunk" and "compute chunk/atom".

I change the line ** (see part of script below):

#------- Thermal conductivity calculation, switch to NVE ------#
variable dt equal 0.0005 # 0.5fs; in picoseconds = 0.5e-12 s
variable W equal 1000 # Swap atoms every this many steps
variable NRUN equal 20000000
variable time equal step*v_dt
variable nslab equal 20
variable slabw equal 1.0/v_nslab

timestep \{dt\} \#\#0\.0005 picosecond = 0\.5 femtosecond thermo {W}
fix NVE all nve
compute ke all ke/atom
variable temp atom c_ke/v_kB/1.5
** fix TEMPP all ave/spatial 1 100000 100000 z lower \{slabw\} v\_temp file tmp\.profile units reduced fix TKE all thermal/conductivity {W} z \{nslab\} swap 1 variable TKEN equal f\_TKE thermo\_style custom step temp pe etotal press pxx pyy pzz f\_TKE run {W}
variable SIflux equal v_TKEN/v_time/v_Area*v_convert
thermo_style custom step temp pe etotal press pxx pyy pzz f_TKE
v_SIflux
thermo_modify flush yes
run ${NRUN}

--------------------------------------------------------------------------------------------------

by two other lines:

compute cc1 all chunk/atom bin/1d z lower ${slabw} units reduced
fix TEMPP all ave/chunk 1 100000 100000 cc1 v_temp file tmp.profile

But I got error message:

ERROR: Unknown fix style (../modify.cpp:782)

​please verify (using -echo screen) which line of your script is giving the
error exactly.
unknown fix style means that LAMMPS cannot find the fix requested. that can
have multiple origins:
- the fix is an optional feature and the package is indeed not included ​
- you have a typo in your input
- you have a non-ascii character in your input, e.g. due to using
cut-n-paste in a non-ascii character encoding.

axel.