[Wien] Interstitial chrge in Supercell

[alpa dashora]

Dear Wien2k users,

I am trying to learn the super cell calculation using Wien2k code. I have
tried the super cell calculation for MgO. I have successfully made the super
cell. I have also compared the band gap of super cell calculation and simple
calculation, both are nearly equal. In case of charge density in case.scf
file, charge of Mg and O atom in supercell calculation is same as obtained
in the simple calculation but the interstitial charge is increased with
large amount.

In MgO.scf:

       CHARGES OF NEW CHARGE DENSITY
:NTO  : TOTAL   INTERSTITIAL CHARGE=  1.3513408
:NTO001: TOTAL   CHARGE IN SPHERE  1 (Mg) = 10.4017583
:NTO002: TOTAL   CHARGE IN SPHERE  2  (O) =  8.2468982

In super.scf

       CHARGES OF NEW CHARGE DENSITY
:NTO  : TOTAL   INTERSTITIAL CHARGE= 11.0052414
:NTO001: TOTAL   CHARGE IN SPHERE  1 (Mg) = 10.3769756  Multiplicity=1
:NTO002: TOTAL   CHARGE IN SPHERE  2 (Mg) = 10.3769756  Multiplicity=1
:NTO003: TOTAL   CHARGE IN SPHERE  3 (Mg) = 10.3769651  Multiplicity=6
:NTO004: TOTAL   CHARGE IN SPHERE  4 (O)  =  8.2472885  Multiplicity=6
:NTO005: TOTAL   CHARGE IN SPHERE  5 (O)  =  8.2474031  Multiplicity=6

Please tell me, why the interstitial charge is very high in both the cases?
-- 
Alpa Dashora
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://zeus.theochem.tuwien.ac.at/pipermail/wien/attachments/20090521/2b1247f5/attachment.html