Hi, I'm not sure I understand exactly what you did. Anyway: put R2V (instead of NR2V) in case.in0 and you get the coulomb potential in a file case.vcoul (format as case.clmval), you can plot it using lapw5, or you can have a look at the spherical symmetric part V_00(r).
Is this what you took in (1) ??? (2) I cannot imagine how one gets a proper coulomb potential form clmsum00 alone. (what about ZZ ??; what should be a "neutral muffin-tin" ???, it can hardly be neutral ??. for sure, the charges from outside the sphere affects the potential inside the sphere. In fact, in lapw0 the coulomb-pot at RMT is determined solely from the plane wave part ! You may have a look at M.Weinert's paper, according to which the potential is calculated. Am 29.11.2011 14:24, schrieb John Rundgren: > Dear Wien2k Team, > This is about vcoul(L,M=0,0) generated by Fe3O4 and Sr3Mn2O7. I compare > two potential curves as functions of radius R: > > (1) VC(R)=vcoul00(R)/sqrt(4*pi), spherically symmetric; > (2) VCpois(R), spherically symmetric, obtained from clmsum00 and > Poisson's equation (using subroutine charg2.f). My boundary condition of > PE is the conventional one giving zero VCpois for a neutral muffin-tin > and large R. > > In summary, I expect that VC and VCpois are equal up to a constant, > individual for individual atoms depending on the SCF boundary condition > in Wien2k. Results for Fe3O4 and Sr3Mn2O7: > > Fe3O4, Table for potential value at RMT: > Fe1 Fe2 O > VC -0.13 0.18 0.37 > VCpois -2.03 -2.08 -1.15 > VCpois(R)=VC(R)+const with great accuracy. > > Sr3Mn2O7 with RMT's from setrmt_lapw, Table for potential value at RMT: > Sr1 Sr2 Mn O1 O2 O3 > VC -472 -382 -231 -258 -230 -250 > VCpois -2.0 -2.0 -2.6 -7.3 -7.5 -7.0 > > First observation: the values differ by factors 35-235. How is the > boundary condition for vcoul defined in Wien2k? > > Second observation: dVC/dR is<0 and dVCpois/dR is>0 for R in the > neighborhood of RMT. Indeed, the latter behavior corresponds to a > muffin-tin with negative charge. > > Third observation: VCpois(R) .neq. VC(R)+const. The disagreement is > significantly great, see 1st Attachment. > > When the Fe3O4 calculation is used for LEED, the agreement > theory-experiment is satisfactory [Surf.Sci. 602(2008)1299]. On the > other hand, a LEED investigation on Sr3Mn2O7 would respond badly on a > potential disagreement like the one demonstrated in the 1st Attachment. > 2nd Attachment is SR3Mn2O7.struct. > > VC versus VCpois is a dilemma for Sr3Mn2O7. Is there an expert's input > to w2web that would make the potentials equal? A discussion would be > much appreciated. > > With best regards, > John Rundgren, KTH, Stockholm > > > > > _______________________________________________ > Wien mailing list > Wien at zeus.theochem.tuwien.ac.at > http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien -- P.Blaha -------------------------------------------------------------------------- Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna Phone: +43-1-58801-165300 FAX: +43-1-58801-165982 Email: blaha at theochem.tuwien.ac.at WWW: http://info.tuwien.ac.at/theochem/ --------------------------------------------------------------------------