Hey,
I wanted to find the vacancy formation energy in Uranium using the EAM potential, but I am getting the same energy before and after the vacancy creation… Can you please check this let me know the error. Thank you…
---------- INITIALIZATION ----------
clear
units metal
dimension 3
boundary p p p
atom_style atomic
---------- LATTICE & REGION ----------
variable a equal 2.84
variable b equal 5.87
variable c equal 4.92
lattice custom 1.0 &
a1 {a} 0.0 0.0 &
a2 0.0 {b} 0.0 &
a3 0.0 0.0 ${c} &
basis 0.0 0.0 0.0 &
basis 0.5 0.5 0.5
region simbox block 0 4 0 4 0 4
create_box 1 simbox
create_atoms 1 box
---------- FORCE FIELD ----------
pair_style meam
pair_coeff * * library-U.meam U U.meam U
---------- COMPUTES ----------
compute eng all pe/atom
compute eatoms all reduce sum c_eng
---------- OUTPUT SETTINGS ----------
reset_timestep 0
thermo 100
thermo_style custom step atoms pe press c_eatoms
---------- MINIMIZE PERFECT STRUCTURE ----------
dump 1 all custom 500 dump.perfect.* id type xs ys zs c_eng
min_style cg
minimize 1e-10 1e-10 5000 5000
undump 1
---------- STORE INITIAL ENERGY ----------
variable N equal count(all)
variable Ei equal c_eatoms
variable No equal v_N
---------- DELETE CENTRAL ATOM ----------
region center sphere 0.5 0.5 0.5 0.01 units lattice
group vacatom region center
delete_atoms group vacatom compress yes
---------- MINIMIZE DEFECTED STRUCTURE ----------
reset_timestep 0
dump 2 all custom 500 dump.vacancy.* id type xs ys zs c_eng
min_style cg
minimize 1e-10 1e-10 5000 5000
undump 2
---------------------- CALCULATE VACANCY ENERGY ------------------
variable Ef equal c_eatoms
variable Ev equal {Ef} - (({No}-1)/{No})*{Ei}
---------------------- PRINT RESULTS -----------------------------
print “-----------------------------------------------------”
print “Total atoms before deletion (N) = {No}"
print "Initial energy (perfect) Ei = {Ei} eV”
print "Final energy (defected) Ef = {Ef} eV"
print "Vacancy formation energy Ev = {Ev} eV