[Wien] about SO coupling parameter

[Victor Pardo Castro]

> Dear Wien2k comunity
> Could somebody explain me how to extract the so coupling parameter from the
> lsda+so calculations?, i didn't find anything posted in the mailing list
> about this.

Maybe there are better ways but I just know how to do it with  
LSDA+U+SO. If you are talking about \lambda, as in H_so= \lambda L.S,  
I would try to flip L with respect to S, which is easy to do in some  
cases playing with the dmat files (probably exchanging m_l occupation  
to -m_l or similar). Without LDA+U I wouldn't know how to do it, but  
once you have the total energy of a configuration with L parallel to S  
and another one with L antiparallel to S, the energy difference  
between them could be approximated to 2 \lambda L.S, and you can  
extract \lambda.

I know \lambda can be extracted from some derivative of the potential  
(I do not know the details), but I do not think that has been  
introduced in the code (some other codes have it, I believe).


Víctor Pardo