Hello lammps users,
I am trying to calculate surface energy of Fe(BCC) (100),(110),(111) surfaces. The potential that I’m using gives me good elastic constants. I am under the impression that good elastic constants means good surface energy. But unfortunately my surface energies are off by the factor of 3. So my question is am I wrong to think that good elastic constants means good surface energy? I am looking for some suggestions. I will be glad to receive some suggestions. Also here is the script I’m using.
units metal
boundary p p p
atom_style atomic
read_data bcc_111_1-10_11-2.lmp
pair_style adp
pair_coeff * * potential_adp Fe
variable E2 equal “pe”
fix 1 all box/relax aniso 0.0001 nreset 10
dump 1 all custom 1 dump.movie id x y z
thermo_style custom pe vol pxx pyy pzz lx ly lz
minimize 1.0e-16 1.0e-16 100000 100000
print “${E2}” append surface.dat screen no
clear
units metal
boundary p s p
atom_style atomic
read_data bcc_111_1-10_11-2.lmp
pair_style adp
pair_coeff * *potential_adp Fe
variable E1 equal “pe”
thermo_style custom pe vol pxx pyy pzz lx ly lz
minimize 1.0e-16 1.0e-16 1000000 1000000
print “{E1}" append surface.dat screen no
print "(lx)” append surface.dat screen no
print “(lz)" append surface.dat screen no
variable temp equal 2*lx*lz
variable E_sur equal (v_E2-v_E1)/v_temp
print "{E_sur}” append surface.dat screen no
Thanking you
Praveen