On Jan 24, 2007, at 9:50 , Miguel Mart?nez Canales wrote: > 1) Is trying to calculate the Debye temperature from the phonon DOS > too na?ve?
It should be possible; for sufficiently isotropic dispersions you might also try to estimate the coefficient c in w(q)=cq for q->0 > 2) What are the practical differences between simple and crystal asr? 'simple' asr consists in modifying the diagonal term only of the force constant matrix so that the sum over all atoms of the induced forces is zero. 'crystal' asr modifies the matrix in such a way to conserve the symmetry, I think. > Could be translated to: What does "optimized corrections of the IFC" > in pwtools/q2r.f90 mean? it means that you have to read the original reference, if any (try this: PRB 71, 205214 (2005) ) > 3) Is the hoop I'm seeing at around 17cm-1 a van Hove singularity I > haven't > covered in my dispersion curves or something more profound? hard to say, especially without seeing Paolo --- Paolo Giannozzi, Democritos and University of Udine, Italy
