Try a negative value of U instead. The definition of +U is not exactly the same in planewave and LCAO.
Hi,
I want to mention that the ATK version I am using is 13.8.1, since our group only bought the license of this version. Does this give a difference?
I tried to use a negative value of U.
Without U, the GGA-PBE (no spin) gives Eg 1.689eV.
With U=-2eV on d orbital of Mo atom only, the GGA-PBE (no spin) gives Eg 1.698eV.
With U=-3eV on d orbital of Mo atom only, the GGA-PBE (no spin) gives Eg 1.691eV.
I tried U=-3eV or U=3eV on both d orbital of Mo atom and p orbital of S atom. The band gap still did not change much.
Anyway, I did not see a large Eg increase of monolayer MoS2.
However, I did LDA+U (no spin) for orthorhombic phase of HfO2.
Without U, the band gap is 4.03 eV.
With U=5eV on d orbital of both Hf and O atoms, the band gap increases to 5.4eV.
Could you give some suggestions on how to get a correct band gap(around 2eV) of monolayer MoS2 using LDA+U or GGA+U?
Thanks.