Dear all, By GGA+U as implemented in QE, the correct magnetization (M) and band gap was obtained. The correct U value for each atom was obtained by intensive step by step runs to reach gradually the experimental M value, and therefore band gap. All results are OK till now (the U value itself also= 3.4 eV for carbon and fluorine is acceptable ). However, by enlarging the obtained U value a bit (to 3.7 eV), the predicted M come back to that of pure GGA. Is it natural, or a problem exist? Best regards, F. Marsusi,