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Subsections
The main postprocessing code pp.x extracts the specified data
from the data files produced by PWscf (pw.x executable) or CP
(cp.x executable); prepares data for plotting by writing them into
formats that can be read by several plotting programs.
Quantities that can be read or calculated are:
charge density
spin polarization
various potentials
local density of states at EF
local density of electronic entropy
STM images
selected squared wavefunction
ELF (electron localization function)
RDG (reduced density gradient)
integrated local density of states
Various types of plotting (along a line, on a plane, three-dimensional, polar)
and output formats (including the popular cube format) can be specified.
Moreover data can be saved to an intermediate (formatted) file so that
more data set can be summed or subracted in a later run.
The output files can be directly read by the free plotting system Gnuplot
(1D or 2D plots), or by code plotrho.x that comes with PostProc
and produces PostScript 2D plots,
or by advanced plotting software XCrySDen and gOpenMol (3D plots).
See file Doc/INPUT_PP.* for a detailed description of the input
for code pp.x.
See Example 01 for an example of a charge density plot, Example 03
for an example of STM image simulation.
Code plan_avg.x calculates planar averages of Kohn-Sham orbitals.
Code average.x calculates planar averages of quantities calculated
by pp.x (e.g. potentials, charge, magnetization densities).
Note that average.x reads the intermediate file produced
by pp.x, not data files produced by pw.x. Examples of usage
of average.x can be found in examples/WorcFct_example/
and in examples/dipole_example/.
pawplot.x produces plots of the all-electron charge
for PAW calculations.
In http://theory.cm.utexas.edu/henkelman/code/bader/
one can find a software that performs Bader's analysis starting
from charge on a regular grid. One should use PAW to compute the
charge density. The required "cube" format can be produced using
pp.x (info by G. Lapenna who has successfully used this
technique, but adds: ``Problems occur with polar X-H bonds or in
all cases where the zero-flux of density comes too close to atoms
described with pseudo-potentials"). This code should perform
decomposition into Voronoi polyhedra as well, in place of obsolete
code voronoy.x (removed from distribution since v.4.2).
Alternatively, you can use CRITIC2, available at
https://github.com/aoterodelaroza/critic2, which can
read directly pw.x output and ``XSF'' files. CRITIC2
functionaly include Bader's AIM, ELF, laplacian of density and
potentials, non-covalente interaction (NCI) plots and much more.
Next: 4.2 Band structure, Fermi
Up: 4 Usage
Previous: 4 Usage
Contents
Paolo Giannozzi
2017-10-23