[QE-users] DFT+U - error when using the pseudopotential projectors

[Paolo Giannozzi]

On 07/12/2022 16:26, Iurii TIMROV via users wrote:

> it might be that something has been broken over the years

it might be, given the complete absence of tests and examples for that 
feature. It isn't, though: with a different pseudopotential 
(Co.pbesol-n-kjpaw_psl.1.0.0.UPF) not containing semi-core states, 
neither the current code nor the first version (5.0.3) implementing 
DFT+U with pseudopotential projectors crash. The results seem to be the 
same (convergence is nasty as usual so it is difficult to get exactly 
the same numbers).

A comment in PW/src/init_q_aeps.f90 seems to confirm that the problem is 
in the logic used to choose the projectors:

   ! NOTE: one might run into troubles when using a PP with semicore
   ! states with same l as valence states (also otherwhere for DFT+Hubbard

Paolo
-- 
Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
Univ. Udine, via delle Scienze 206, 33100 Udine Italy, +39-0432-558216