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Hi,

Sometimes it is necessary to make a comparison between structures one calculates and experimental STM pictures (e.g. when there is no other geometric information available). To do this I need to get my hands on the LDOS, not the one you find in the DOSCAR file but the square of the wavefunction.

1) are there any tools available to extract the wavefunctions in a usefull format from the WAVECAR file?
2) What is the actual format of the WAVECAR file such that I could extract the wavefunctions myself from this file?

Thx
Danny

with VASP it is possible to calculate STM pictures within the Tersoff-Haman approach (PRB31, 805, 1985) in an (almost) standard run:
1) calculate the decomposed charge density for the energy range corresponding to the experimental bias voltage (please check if the experiment was done under tunneling or reverse tunneling conditions!) , using the
LPARD= True
EINT= (set the energy range of the states that contribute to the tunneling current)
then plot the isosurface of the charge density of the PARCHG file at the tip-apex/ surface distance (to simulate constant-current images).
please find a more detailled explanation of the LPARD option in http://cms.mpi.univie.ac.at/vasp/vasp/node138.html
There is a visualization tool (STREender) developed by Dr. Daniel Spisak (in this group) which can be downloaded from his
homepage to do so (http://cms.mpi.univie.ac.at/spisak)
please inform him if you decide to use this package, his email-address is
daniel.spisak@univie.ac.at

The Tersoff-Hamann approach was the one I intended to use already. The option in VASP though was unknown to me, thank you for that information .

Seeing the output it is supposed to generate(I already wrote a contourplot program in the past) I now have everything I need.

Thx again.
Danny