On 11/08/2017 15:10, Tan Hengxin wrote: > My value is just ~2.1 eV. > Maybe my norm-conserving pseudopotentials (NC-PPs) of Zn and O > are not very good. So I also tried the NC-PPs for Zn and O from > the pslibrary.0.3.1. However, the gap is even smaller (~1.8 eV). > (All PPs are based on PBE xc.)
This already tells you that the pseudopotentials are certainly a problem. You might have also other problems, of course - but these are one. Where do the original ones come from? (the ones that give you 2.1)? After having seen the SSSP tests I would try the Zn and O from SG15, at ~100 Ry: http://www.quantum-simulation.org/potentials/sg15_oncv/ Can you report what you get? Thanks, nicola -- ---------------------------------------------------------------------- Prof Nicola Marzari, Chair of Theory and Simulation of Materials, EPFL Director, National Centre for Competence in Research NCCR MARVEL, EPFL http://theossrv1.epfl.ch/Main/Contact http://nccr-marvel.ch/en/project _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
