Further tests have shown, that changing the mixing method (e.g. MSEC to PRATT) as well as changing the mixing parameter results in slight changes in total energy, but it is still about -0.2 Ry.
lstart doesn't really generate zero density, so I did it by hand setting all values of Clm coefficients in *clm* files to zero. That was my starting density which equals to the real one. then i did an "infinite" loop by running runsp_lapw -ec 0.0 -i 1000 The result was that the final density remained zero, but the total energy remained -0.2 Ry. I understand, that this is a kind of implementation artefact which can't be avoided. My real question is whether this can somehow influence on the results of the following calculations: 1. the systems where the hydrogen has +1 charge (e.g. hydrogen fluoride, HF) 2. the systems where the hydrogen is H-, but one electron is removed and it becomes a proton (btw, is it possible to add or remove an electron from the particular atom?) -- Yurko (aka Yuriy, Iurii, Jurij etc) Natanzon PhD student Department for Structural Research (NZ31) Henryk Niewodnicza?ski Institute of Nuclear Physics Polish Academy of Sciences ul. Radzikowskiego 152, 31-342 Krakow, Poland E-mail: Yurii.Natanzon at ifj.edu.pl, yurko.natanzon at gmail.com