Dear lammps users and developers,
I’m trying to use fix/adapt and compute/fep commands to get the work of adhesion between water and metallic substrates.
This is the fep part of the script:
1 is Ge, 3 is Ow. Lj with lj/cut between the two.
variable lambda equal ramp(1.0,0.0)
variable dlambda equal -0.05
variable epsilon equal 0.0074437*v_lambda
variable Nadapt equal 100000
variable Nevery equal 40
variable Nrepeat equal 2000
fix ADAPT all adapt/fep {Nadapt} pair lj/cut epsilon 1 3 v_epsilon & after yes fix PRINT all print {Nadapt} "adapt lambda = {lambda} epsilon={epsilon} "
compute FEP all fep 298.15 pair lj/cut epsilon 1 3 v_epsilon
fix FEPAVE all ave/time {Nevery} {Nrepeat} ${Nadapt} c_FEP[1] c_FEP[2] file fep_solo_10_400fep.lmp
The output of the fep is like:
(U1-U0)i
-2.3505
-2.2054
-2.0238
-1.8169
-1.6672
-1.5290
-1.3498
-1.1950
-1.0947
-0.9526
-0.7881
-0.7340
-0.5354
-0.4497
-0.3431
-0.2567
-0.1775
-0.0902
-0.0473
Which sums up to -19.6 eV–>577 mj/m^2 of work of adhesion, definitely too much.
Am i missing something in the post-interpretation or in the command?
input file and fep output attached
Any hints would be appreciated.
fep_1.lmp (595 Bytes)
in_1.lmp (3.07 KB)