PAW :Bloِechl and Kress formulation

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hicpalm
Posts: 44
Joined: Tue Feb 09, 2010 4:33 pm

PAW :Bloِechl and Kress formulation

Post by hicpalm » Thu Sep 30, 2010 10:28 am

hello,
At the end of the following paper : "Electronic structure packages: Two implementations of the projector augmented
wave (PAW) formalism Marc Torrent, N.A.W. Holzwarth, François Jollet, David Harris, Nicholas Lepley, Xiao Xu,
Compyuter Physics Communications 181 (2010) 1862-1867." one can read :

" A new version of ABINIT has been prepared and will be available in production release 6.1
and higher which has the option of using the Bloeِchl exchange-correlation formulation."

question :
- How to switch from Bloِechl to Kress formulation ? is there any input variable for this ?
thanks.

david.waroquiers
Posts: 138
Joined: Sat Aug 15, 2009 12:45 am

Re: PAW :Bloِechl and Kress formulation

Post by david.waroquiers » Thu Sep 30, 2010 11:45 am

Hi,

The difference between the two formulations resides in the computation of the exchange-correlation terms. In the Bloechl formulation, the exchange-correlation potential does not include the compensation charge density whereas in the Kresse formulation, the potential includes the compensation charge density. You can choose between the two formulations thanks to the input variable usexcnhat (see http://www.abinit.org/documentation/helpfiles/for-v6.2/input_variables/varpaw.html#usexcnhat).

David

hicpalm
Posts: 44
Joined: Tue Feb 09, 2010 4:33 pm

Re: PAW :Bloِechl and Kress formulation

Post by hicpalm » Thu Sep 30, 2010 3:07 pm

hi,
many thanks.

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