Hi,all users of wien2k: What is the meaning of the row in the file of case.scf? :NEC01: NUCLEAR AND ELECTRONIC CHARGE 720.00000 719.99823 1.00000 You know the result of 720.00000 minus 719.99823 is 0.00177.However,the last item of the listed row of case.scf is 1.00000.Why? Best regards.