# [Wannier] Library mode

Jürgen Wieferink wieferink at uni-muenster.de
Mon Nov 26 10:02:08 CET 2007

Hello,

to understand the adsorption of organic molecules on silicon and
silicon carbide surfaces I have interfaced our density functional
code to wannier90 (v1.0.2) as a post-processing tool.  It is really
great how little work is needed to get centres and plots of Wannier
functions.  Nevertheless, I have a few questions I don't know where

One question at this stage: Plotting the Wannier functions only
works when I write \psi_{n,k}(r) instead of u_{n,k}(r) to UNK000*.1.
Is this intentional or do I do anything wrong somewhere else?

On the long run, I want to use our own visualization methods.  So I
need the information about the centres and the unitary
transformations within our code.  Using the library mode seems to be
the easiest way.  Thus, I have had a look into the source code and
have a few questions.

One has to provide the M_matrix to wannier_run() without an explicit
reference to nnlist and nncell.  Do I have to rely on the fact that
wannier90 will generate these lists in exactly the same order?  And
secondly it seems that the centres and spreads are not really passed
to the caller after being reset.  I could fix this for myself by
making rave and r2ave global and passing it to wann_centres and
friends.  Or is this fixed in a more recent release?  Or am I wrong
anyway?

Juergen

--
Juergen Wieferink
AG Pollmann
Institute of Solid State Physics
University of Muenster