[gpaw-users] Water dimer energy is computed wrong

[Yuri]

I'm performing this computation:


---HPAW python---

from gpaw import GPAW, PW
import ase.io

def ev2hartree(energy):
     return 27.21138602*energy

h2 = ase.io.read("H2O-dimer.xyz")
h2.center(vacuum=2.5)
h2.set_calculator(GPAW(mode='lcao', basis='dzp', txt='h2o-dimer.txt'))
print(ev2hartree(h2.get_total_energy()))


---H2O-dimer.xyz---

Water dimer
O -1.456 0 0
H -1.78607530591 -0.759608197739 -0.482062826151
H -1.78607530591 0.759608197739 -0.482062826151
O 1.456 0 0
H 0.496537604394 0 0.0923857208542
H 1.78845259152 0 0.903855922824


It returns E=-758.3970356319126 H.


This is different from E=-152.899572664521 H returned by this NWChem script:

start oh-dat
  echo
  geometry noautoz units angstrom
    load H2O-dimer.xyz
  end
  basis
    * library aug-cc-pvdz
  end
  dft
    odft
    xc b3lyp
  end
  task dft energy


And different from E=-152.89661481 H returned by this Erkale script:

System H2O-dimer.xyz
Method hyb_gga_xc_b3lyp
Basis aug-cc-pVDZ


I believe that the correct answer is E=-152.89... H


What is wrong with the GPAW script?

https://wiki.fysik.dtu.dk/gpaw/ says that lcao performs atom-centered 
computations. Why is the result different then?


Yuri