Preliminaries¶
Welcome to wannier90! The examples contained in these tutorials are
designed to help you become familiar with the procedure of generating,
analysing and using maximally-localised Wannier functions (MLWFs). As a
first step, install wannier90 following the instructions in the
README file of the wannier90 distribution. For an introduction to
the theory underlying MLWFs, you are encouraged to refer to the brief
overview given in the wannier90 User Guide,
to the two seminal papers of Refs. 12, a recent
review article 3 and to a paper 4 describing
wannier90.
The following additional programs may be installed in order to visualise
the output of wannier90 (they are optional, not all of them are
necessary)
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gnuplotis used to plot bandstructures. It is available for many operating systems and is often installed by default on Unix/Linux distributions
http://www.gnuplot.info -
xmgracemay also be used to plot bandstructures.
http://plasma-gate.weizmann.ac.il/Grace -
XCrySDenis used to visualise crystal structures, MLWFs, and Fermi surfaces. It is available for Unix/Linux, Windows (using cygwin), and OSX. To correctly display files fromwannier90, version 1.4 or later must be used.
http://www.xcrysden.org -
vmdcan also be used to visualise crystal structures and MLWFs.
http://www.ks.uiuc.edu/Research/vmd -
pythonwith thenumpyandmatplotlibmodules is used in tutorials 17 19
http://www.python.org
http://www.numpy.org
http://matplotlib.org
Parallel execution¶
postw90.x and wannier90.x can
be run in parallel to speed up the calculations, using the MPI
libraries.
To enable the parallel version to be built, you must specify some flags
in the make.inc file of wannier90 and postw90; for further
information, please refer to the README.install file in the top
directory of the wannier90 distribution.
Then, to run e.g. with 8 processors, you typically need to run a command
similar to postw90 as follows:
(the mpirun command and its flags may differ depending on the MPI
libraries installed on your system: refer to your MPI manual and/or to
your system administrator for further information).
About these tutorials¶
The first part of this collection of tutorials comprises four examples taken from
Refs. 12: gallium arsenide, lead, silicon
and copper. All of the wannier90 input files have been provided.
The second part of this collection of tutorials covers the generation of
wannier90 input files starting from a full electronic structure
calculation. We have provided input files for the
pwscf interface (http://www.quantum-espresso.org) to
wannier90. Therefore, you will need to install and compile elements of
the quantum-espresso package, namely pw.x and pw2wannier90.x, in
order to run these tutorials. Please visit
http://www.quantum-espresso.org to download the package, and for
installation instructions.
There are interfaces to a number of other electronic structure codes including abinit (http://www.abinit.org), fleur (http://www.flapw.de), OpenMX (http://www.openmx-square.org/), GPAW (https://wiki.fysik.dtu.dk/gpaw/), VASP (http://www.vasp.at), and Wien2k (http://www.wien2k.at)
Contact us¶
If you have any suggestions regarding ways in which these tutorials may be improved, then send us an email.
For other questions, email the wannier90 forum at
wannier@quantum-espresso.org. Note that first you will need to
register in order to post emails. Emails from non-registered users are
deleted automatically. You can register by following the links at
http://www.wannier.org/forum.html.
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N. Marzari and D. Vanderbilt. Maximally localized generalized wannier functions for composite energy bands. Phys. Rev. B, 56:12847, 1997. ↩↩
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I. Souza, N. Marzari, and D. Vanderbilt. Maximally localized wannier functions for entangled energy bands. Phys. Rev. B, 65:035109, 2001. ↩↩
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N. Marzari, A. A. Mostofi, J. R. Yates, I. Souza, and D. Vanderbilt. Rev. Mod. Phys., 84:1419, 2012. ↩
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A. A. Mostofi, J. R. Yates, Y.-S. Lee, I. Souza, D. Vanderbilt, and N. Marzari. Wannier90: a tool for obtaining maximally-localised wannier functions. Comput. Phys. Commun., 178:685, 2008. ↩