VASP Forum

If I havn't experiment date in hand, how can I get the accurate bandgap in the strongly correlated system? Or can I calculate out the value of U and J by VASP?

U and J have to be given explicitely as input, they cannot be obtained from VASP. If you can't find data in the literature, please do a series of runs, varying U and J, and choose the values which are best to reproduce the experimental results (band gaps)... for your study