On Mar 8, 2011, at 24:28 , Tram Bui wrote: > I have post a question regarding the single atom calculation > for carbon simple cubic system last month [...] the calculation > ran fine using espresso-4.1.3 (older version), but not for > espresso-4.2.1 (latest version)
the old version used to symmetrize tha charge density also for the Gamma case. The new version doesn't (it shouldn't be needed in principle). The problem is that in the specific case of atoms, you may have degenerate levels. The resulting charge density is in general not spherical. If you force it top be spherical, the code quickly converges to a solution. If you don't, it doesn't. This is a problem that arises only in isolated atoms, so I wouldn't attach much importance to it. And no, it is not a bug, contrary to what I said in a previous message. Paolo --- Paolo Giannozzi, Dept of Chemistry&Physics&Environment, Univ. Udine, via delle Scienze 208, 33100 Udine, Italy Phone +39-0432-558216, fax +39-0432-558222
