There are several versions (at least six) of the LDA/GGA+U method and one of them is SIC, which is also called fully localized limit (FLL) or atomic limit in the literature.
The SIC method used in Szotek et al. [PRB 74, 174431 (2006)] is not a LDA/GGA+U method. This is the method of Perdew and Zunger [PRB 23, 5048 (1981)], where all electrons (and not only d-electrons) have their self-interaction error corrected. This paper gives a very good summary of the different versions of LDA/GGA+U: http://prb.aps.org/abstract/PRB/v79/i3/e035103 On Fri, 14 Oct 2011, shamik chakrabarti wrote: > Dear wien2k users, > > If we use exchange correlation potential GGA and > modify case.inorb in such a way that nmod=1 and nsic=1 (SIC method, Anisimov > et al) then what we are using: > > *GGA+U or self interaction corrected GGA?...or they are actually different > terminology of the same thing?* > > I am asking this question because in a paper (PRB, vol. 74, 174431(2006)), > the authors told that they have used GGA+U once and then SIC-GGA....so > whether they are different?..if they are different then what is the > difference?...can you please suggest some reference... > > Any response will be very helpful for us. Thanks in advance. > > with best regards, > -- > Shamik Chakrabarti > Senior Research Fellow > Dept. of Physics & Meteorology > Material Processing & Solid State Ionics Lab > IIT Kharagpur > Kharagpur 721302 > INDIA >