[gpaw-users] Cu2O dipole corrections - convergence problems

[Man Isabela]

Dear all,

I am trying to do some calculations on different Cu2O surfaces (100, 110, 111 surfaces and for each different surface terminations). 
For all cases I encounter the same problem. When I do not apply dipole corrections , everything is fine and I get the convergence. When I apply it, depending on surface after none, one or two steps the energy become positive. 

mixer=Mixer(0.1, 5, weight=100.0)
calc = GPAW(h=0.2,
                                xc='RPBE',
                                txt=outid,
                                kpts=(2,2,1),
                                #eigensolver='cg',
                                width=0.10,
                                #verbose=True,
                                mixer=mixer,
                                nbands = -30,
                                spinpol = False,
                                usesymm = False)
poissonsolver = PoissonSolver()
correction = DipoleCorrection(poissonsolver, 2) # 2 == z-axis
calc = GPAW(poissonsolver=correction)
calc.attach(calc.write,1,gpwdat)
slab.set_calculator(calc)

I have attached also one of the output file and the corresponding structure.
I haven't tried yet to run first in the LCAO mode and than to continue this way.

Thank you
Isabela Man
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