[Wien] Interstitial doping

[Stefaan Cottenier]

>           How to do interstitial doping calculations in WIEN2K?there is
> no introduction in UG and little information in mailinglist.
>           I tried to do the interstitial doping by adding an atom
> through structgen, when sgroup, the original symmetry is broken, and the
> space group turns to be 1p1, and the x symmetry implies:error, negative
> position in rstruct.

First you decide on the original undoped (super)cell you want to use. 
Then figure out at which coordinates the dopant should be in that cell. 
Next, either insert that position manually (increase the number of 
inequivalent atoms atoms (line 3) by one, and add the entire block with 
position info etc. for the extra atom), or use makestruct_lapw to 
generate the entire (super)cell again from scratch, with the impurity.

sgroup will indeed break the symmetry, that is normal. Accept its 
proposal, and symmetry will not complain afterwards.

Stefaan