Problem with meta GGA calculation with TPSS functional
Posted: Wed Aug 19, 2015 1:16 pm
Hello All.
What has changed concerning the meta GGA implementation in the new VASP version 5.4.1 in comparison to VASP 5.3.5?
This question arised for example when calculating bcc-iron with the TPSS functional in both versions: We get an energy(sigma->0) of -30.88694853 eV with the new version, an energy of -30.85589926 eV with the old version (both after fully optimizing the structures). Moreover, when starting a run using the new version 5.4.1 with a structure fully converged with the TPSS functional in the old version 5.3.5, the new version starts doing a lot of structural optimization steps (>50) which should not be necessary at all.
So, the question is: was the old version buggy, should we throw away all old calculations?
Or is there maybe something wrong with the new version?
This does not happen with the PBE functional, only with the TPSS one.
Thank you very much in advance.
BECK
What has changed concerning the meta GGA implementation in the new VASP version 5.4.1 in comparison to VASP 5.3.5?
This question arised for example when calculating bcc-iron with the TPSS functional in both versions: We get an energy(sigma->0) of -30.88694853 eV with the new version, an energy of -30.85589926 eV with the old version (both after fully optimizing the structures). Moreover, when starting a run using the new version 5.4.1 with a structure fully converged with the TPSS functional in the old version 5.3.5, the new version starts doing a lot of structural optimization steps (>50) which should not be necessary at all.
So, the question is: was the old version buggy, should we throw away all old calculations?
Or is there maybe something wrong with the new version?
This does not happen with the PBE functional, only with the TPSS one.
Thank you very much in advance.
BECK