profile.lmp

################################################################################
# GRAPHENE: POTENTIAL PROFILE
################################################################################
#
# Input script for lammps to calculate the potential energy in function of the
# distance between carbon atoms in a graphene layer.
#
# When using this script, make sure that lammps is installed with the USER-REAXC
# and the MANYBODY packages.
#
# Date: 28/03/2016
# Author: Jeroen Mulkers
# Mail: jeroen.mulkers@uantwerpen.be
#
################################################################################


# UNITS
# 'real' units are needed when using reax/c. A useful energy conversion factor
# is defined.
units        real
variable     fenergy equal 0.043 # Kcal/mole -> eV

# GRAPHENE SHEET
# The atom positions and the simulation box size will be read from a data file.
# Reactive force fields (reaxFF) are used to describe the interaction between
# the carbon atoms.(The pair_style reax is deprecated. so we use the modern
# reax/c implementation)
dimension    2
boundary     p p p
atom_style   charge
read_data    graphene.dat
pair_style   reax/c NULL checkqeq no
pair_coeff   * * ffield.reax C

# OUTPUT
# Calculate the average total energy per atom and the distance 'a' between
# carbon atoms in two ways (should give the same size)
variable     energy equal etotal/atoms*${fenergy}
variable     a1 equal lx/3
variable     a2 equal ly/sqrt(3)
thermo_style custom step etotal pe ke v_energy v_a1 v_a2 pxx pyy

# DEFORMATION
fix          1 all deform 1 x erate 0.001 y erate 0.001 remap x
thermo       1
run          2000