Dear Ali,
Just a few additional words:
The symmetric dielectric matrix is given in the output file generated
by the binary head.x (based on the ph.x phonon code as Paolo said). In
particular, it is also given by the second number on the line starting
by "HEAD:" .
In other words, if you do a
Dear Ali,
First of all, note that the GWW is implemented only at the gamma point,
so it requires large supercells, (or better it is appropriate for
non-crystalline systems).
However the long-range parts of the symmetric dielectric matrix
and of the screened-interaction can be calculated using k-po
