Dear Paolo,
Thanks for your response. But i am not sure i understand it
completely. Are you implying that "g" cannot be calculated for a particular
phonon (of specific q and nu) ? I am not entirely familiar with the concepts of
irreducible representation. But in the expression for "g", there is a
omega_nu,q and also the derivative of V_SCF with respect to displacement along
a particular nu for a given q. Thanks Ajit
