<html><head><meta http-equiv="Content-Type" content="text/html; charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">I am wondering why I get a negative rho message for GBRV pseudopotentials, particularly for HfO2. It does not get better<div class="">by increasing ecutrho, and get worse (scales) with larger supercells. I have tried lda, pbe, and pbesol and they all give this effect:</div><div class=""><br class=""></div><div class=""><div class=""> negative rho (up, down): 4.585E-01 0.000E+00</div><div class=""><br class=""></div><div class="">An example is attached. I do not find this for all atoms. Is this a problem to worry about, and if so how to fix?</div><div class="">It does not depend on the version of qe. With ONCV pseduopotentials I see no problems.</div><div class=""><br class=""></div><div class="">Sincerely,</div><div class=""><br class=""></div><div class="">Ron</div><div class=""></div></div></body></html>