[Pw_forum] Berry Phase calculation for gdir=1,2 ; cvs version

[umari at democritos.it]

Dear Jess,

It could be that k points where not string along the same direction 
defined by gdir,
In the sense, let's suppose nppstr=3
if gdir=3, you should have something as
K_POINTS (crystal)
N   number of total k_points
0.  0.   0.   1.
0.  0.   0.333333  1.
0.  0.   0.666666  1.
0.5 0.   0.        1.
0.5 0.   0.3333333 1.
0.5 0.   0.6666666 1.
...and so on...

if for examples gdir = 1, the strings of 3 k_points must be in the
direction 1, as:

K_POINTS (crystal)
N   number of total k_points
0. 0.     0.      1.
0.333333  0.  0.   1.
0.6666666 0.  0.     1.
0.        0.5 0.    1.
0.333333  0.5 0.   1.
0.6666666 0.5 0.  1.
...and so on..


note that if gdir=i you are applying the electric field
in the direction parallel to the i-th vector of the
direct lattice. The electronic polarization is
also given on that axis.
The value for the ionic polarization is still not correct,
but a cvs commit should arrive today or tomorrow.


Paolo Umari

Democritos, Trieste


----------------------------------------------------------------
This message was sent using IMP, the Internet Messaging Program.