<!DOCTYPE html>
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
</head>
<body>
<p><font face="Comic Sans MS">Hello !</font></p>
<p><font face="Comic Sans MS">I am doing a phonon calculation with
one of my structure, but I always have the following error <br>
</font></p>
<p><font face="Comic Sans MS">" Electric Fields Calculation<br>
kpoint 1 ibnd 425 solve_e: root not converged 1.291E-02<br>
kpoint 1 ibnd 425 solve_e: root not converged 1.961E-02<br>
kpoint 1 ibnd 425 solve_e: root not converged 9.242E-03<br>
kpoint 2 ibnd 425 solve_e: root not converged 2.195E-02<br>
kpoint 2 ibnd 425 solve_e: root not converged 1.554E-02<br>
kpoint 2 ibnd 425 solve_e: root not converged 1.200E-02<br>
<br>
iter # 171 total cpu time : 1405.0 secs av.it.: 192.3<br>
thresh= 1.000E-02 alpha_mix = 0.500 |ddv_scf|^2 =
5.291E+57<br>
kpoint 1 ibnd 425 solve_e: root not converged 1.993E-02<br>
kpoint 1 ibnd 425 solve_e: root not converged 7.971E-03<br>
kpoint 1 ibnd 425 solve_e: root not converged 1.208E-02<br>
kpoint 2 ibnd 425 solve_e: root not converged 1.705E-02<br>
kpoint 2 ibnd 425 solve_e: root not converged 8.628E-03<br>
kpoint 2 ibnd 425 solve_e: root not converged 1.024E-02
"<br>
</font></p>
<p><font face="Comic Sans MS"><br>
</font></p>
<p><font face="Comic Sans MS">It seems from previous similar error
in the forum, that I have to play a bit with the value of
alpha_mix (I have tried with bot alpha_mix=1.00 and
alpha_mix=0.500) and I have to reduce the value tr2_ph (I am
using 1e-7 at the moment).</font></p>
<p><font face="Comic Sans MS">So far anything did change and this
error always appears. I see also that the |ddv_scf|^2 (is ti one
of the element of the hessian ?) it totally crazy. Honestly my
structure seems to be very reasonable and easely converges with
an SCF calculation.</font></p>
<p><font face="Comic Sans MS">Is there some suggestion to overcome
this problem ? <br>
</font></p>
<p><font face="Comic Sans MS">Thanks,</font></p>
<p><font face="Comic Sans MS">Marco <br>
</font></p>
</body>
</html>