Hi all.
I have a question concerning the use of the optical K mesh in siesta to calculate the dielectric function: is the optical K mesh independent from the number of the usual kgrid mesh used for the relaxation of the system? If I have a system which density matrix has been calculated with 32kpt let's say, then the way I choose� the optilcal k mesh is independent from this or not? The optilcal k mesh define the numeber of k points which enters directly into the sum to calculate through the "fermi golden rule" the eps2, the imaginary part of the dielectric function. So since the spectra has to be converged w.r.t� number of bands and number of k points, I presume i can augment each time the Optical K mesh until the convergence is reached. in this way I presume the choose of optical K mesh is independent from the kgrid mesh used before in the scf part. Is this correct ? Thanks a lot and enjoy the hot summer time! :) -- Dr. Federico Iori, PhD! Dipartimento di Scienze e Metodi per l' Ingegneria (DISMI) Universita' di Modena e Reggio Emilia Via Amendola,2 Pad. Morselli 42122 Reggio Emilia (Italy)
