[Pw_forum] Induced charge density, phonon.

[Vasile Chis]

Dear users.

I was wondering if I could get some help regarding the induced charge
density at a surface due to a phonon at a specific q-point.

The surface is based on the slab model.

For a specific mode (surface mode) at a specific q-parallel-point (SBZ
zone boundary) I would like to extract the induced charge density in
real space along the slab z-axis, delta-n(R,z) where R=(x,y) (a point i
the slab plane).

I have tried with some lighter examples to use and try to understand the
option in INPUT_PH namely fildrho. All this gave was a lot of zeros,
regardless at which q-point this was done. Any explanations why?

I've would be pleased for any ideas of how to access this problem and
how to get the desired charge density in real space.

Thank you in advance.

Best regards
Vasse 
-- 
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  Vasile Chis, Ph.D Student
  Interface Modelling Group
  Department of Physics
  Göteborgs Universitet
  Fysikgården 6B
  S-412 96 Göteborg, SWEDEN
  tel    :+46 (0) 31 7723338
  mobile :+46 (0) 70 8348867
  fax.   :+46 (0) 31 7723367
  email  :Vasile.Chis at physics.gu.se
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