<html>Dear all,<br />Is there a way to perform a phonon calculation only for the lowest phonon frequency for exemple by using the Lanczos algorithm?<br /><br />I mean to test the dynamical stability of a structure, one only need to know that "all the frequencies are positives over the full BZ",<br />which is the same as "no frequencies are negatives" and in this case, one only need to know the lowest value of all the phonons frequencies.<br />For the biggest structures with a too big dynamical matrix, the phonon DOS have a too high computationnal cost and this trick should be very usefull...<br /><br />Best regards,<br /><br />Antoine Jay<br /> </html>