[Wien] 2 ways to calculate bindning energy

[Lyudmila Dobysheva]

Tuesday 11 March 2008 21:02 B. Yanchitsky has written:
> Ev_super = E[N-1] - (N-1)*E[1].      (1)
> Ev_atom = Ei - E[1].                          (2)

I cannot quite catch the problem: do you expect these values equal?
If you multiply by n-1
(N-1)Ev_atom = (N-1)Ei - (N-1)E[1].                 (2')
in the first formula you have energy of N-1 atoms in a defect supercell as a 
first term in subtraction. In the second formula you have energy of N-1 
isolated (far from each other) atoms as a first term. What puzzles you? Or I 
do not understand something?

Best regards
Lyudmila Dobysheva
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