<html><head><meta content="text/html; charset=windows-1252" http-equiv="Content-Type"></head><body><div><div style="font-family: Calibri,sans-serif; font-size: 11pt;">Thanks to both Giuseppe Mattioli and Pang Gui for their help!!! <br>However, I need to ask one more question about the process for obtaining Hubbard coefficients: I follow the tutorials posted with the links, but a thing wasn't clear to me. After scf simple calculation, I need to "perturb" the system in a range between -0.1 & 0.1 eV. But: do i need to save a file for every perturbation induced to the system?<br>How can i set to QE to take every previous result and compute the U term?<br>Be patient, but I'm alone and i trying to do the best for my thesis!!!<br>Best regards,<br>Tommaso.<br></div></div></body></html>