I am stuck with a basic error and can’t seem to find out a way out of it. Will be nice if anyone of you can help.
I performed equilibriation of two graphene sheets, one pure and the other doped (10%with C-14). After equilibriation, I created restart files and then started thermal conductivity calculations using “fix thermal” command for both of the cases for 8ns timestep.
In the last 1ns, I used “fix ave/spatial” to average the bin values over timescales and they were written to a file. Then when I am plotting the “Temp vs x” graphs, an inverted V shape plot (supposedly the correct shape) is coming for the pure graphenes but there is a lot of scatter in the “T vs x” plots for doped cases, which is incorrect. I ran this for a few lengths of graphenes, and in all the cases, the T vs x plots in cased of the doped graphenes came out to be incorrect.
I dont understand why this is happening. The only difference between the 2 cases are the data.graphene files. Or else I am using the same input script. Can anybody please help me sort this problem out? Thank You.
My input file (also attached) is as follows:
#Thermal Conductivity of Graphene Using Tersoff potential
pair_coeff * * SiC.tersoff C C
group Carbon type 1
variable t equal 150000
fix NVT all nvt temp 300.0 300.0 0.1
compute ke Carbon ke/atom
variable temperature atom c_ke/(1.5*8.617e-5)
fix thermal all thermal/conductivity 300 x 100
thermo_style custom step temp pe ke etotal press lx ly lz f_thermal
fix TEP all ave/spatial 1 100 100 x lower 3 v_temperature file temp.graphenedoped20 units box
The output (log.thermal)is also attached below.
SiC.tersoff (1.53 KB)
equil.restart2 (283 KB)
in.graphenethermal (725 Bytes)
log.thermal (9.27 KB)