Dear all, using the phonon code I noticed that, even for simple molecular structures, the dynamical matrix computed by ph.x is not symmetric. (I limited myself to Gamma point calculations.)
In general, this does not guarantee real eigenvalues. How are the eigenfrequencies computed then? Thanks for your time, Cristian -- ___________________________________________________ Cristian Degli Esposti Boschi CNR, CNISM, Unita' di Ricerca di Bologna, c/o Dipartimento di Fisica, Universita' di Bologna viale Berti-Pichat, 6/2, 40127, Bologna, Italia tel. ++39 051 2095114 fax ++39 051 2095113 e-mail: cristian.degliesposti -AT- unibo.it web: http://www.df.unibo.it/fismat/theory ___________________________________________________
