[gmx-users] Energy profile of a single water molecule on Ni surface

[Alexander Alexander]

Dear Gromacs user,

I am a new user trying to produce the energy profile of a single water
molecule on Ni(111) surface, I mean adsorption energy of water molecule on
surface VS the distance of the molecule to surface. The goal is to compare
such a profile with the same profile out of DFT.

Adsorption energy in DFT is defined as:
 {Ad_energy = [Total energy_(water-surface)] -  [Total energy_(surface)] -
[Total energy_(water)]}

How can I calculate the adsorption energy in MD - gromacs? Which one I
should choose out of "gmx energy -f case.edr ....?  "Total-Energy" or
"LJ-(SR)" or Potential energy ... .

After lots of effort navigating the gromacs manual I could manage the
attached inputs file for my calculations, but to be honest,  I really don't
know how my results are reliable. So, to improve my input files and comment
and suggestion are highly welcome.

Thank you so much in advance.

Cheers,

Alex