Dear all, I've been having problem with electron-phonon calculation. I keep having negative phonon frequency in gamma point, -0.00007, nowhere else, (so it is not "real" instability, but some numerical problem) but it keeps interfering with my lambda.x calculation and all i get is NAN for alpha2F and so on. So is there any trick to avoid it? This is clearly numerical issue, because other modes are positive and phonon dispersion looks as it should be and there is no any instability. Can I somewhere manually change that -, maybe? I've tried to increase tr2_ph (and decrease it, also) but it keeps happening just the same. And tried larger k and q grid. Still the same.
Best Regards, PhD Student J.Pesic Center for Solid State Physics, Institute of Physics Belgrade, Serbia _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
