# sumo-bandplot¶

sumo-bandplot is a program for generating publication-ready band structure diagrams. A large number of features are provided, including the ability to project orbital contributions on to the band structure.

## Usage¶

The full range of options supported by sumo-bandplot are detailed in the Command-Line Interface section, and be can be accessed using the command:

sumo-bandplot -h


To plot a band structure, simply run the following command in a folder containing a vasprun.xml or vasprun.xml.gz file, which has been calculated along a high-symmetry path:

sumo-bandplot


The plot will be written to a file named band.pdf, with the raw band structure data written to band.dat.

For example, if we run the command in the sumo/tests/data/Cs2SnI6/bandstructure directory, the band structure should look like:

### File Searching¶

sumo-bandplot will automatically look for vasprun.xml or vasprun.xml.gz files in the current directory. If the band structure has been broken up into multiple parts (as is common for hybrid band structure calculations), these files will be preferentially used. For this to work, the folders should be named split-0* and sumo-bandplot should be run in the folder containing the splits. For example, if the file structure is as follows:

bandstructure/
split-01/
KPOINTS
vasprun.xml
split-02/
KPOINTS
vasprun.xml


sumo-bandplot should be run in the bandstructure directory.

### Basic Options¶

To specify a particular vasprun.xml to plot, the --filenames option can be used. If multiple vasprun.xml files are provided, they will be combined into a single band structure.

The valence band maximum and conduction band minimum can be highlighted using the --band-edges option.

The height, and width of the graphic, along with the y-axis limits, can be controlled via the --width, --height, --ymax, and --ymin options. For example, the plot above could be made more appealing using the following command:

sumo-bandplot --width 4 --ymin -4 --band-edges


### Combined Band Structure and Density of States Plots¶

sumo-bandplot can be used to simultaneously plot a band structure and density of states, using the --dos option. A vasprun.xml to use for the density of states information is required as input. For example, if we run the following command in the sumo/tests/data/Cs2SnI6/bandstructure folder, the output will look like:

sumo-bandplot --dos ../dos/vasprun.xml.gz --ymin -4


Many options are provided for controlling the density of states output. The usage of these options is the same as in sumo-dosplot and described in more detail on the sumo-dosplot page.

To control the number of items that appear in the legend, see Legend Labels.

For plotting specific orbital or atomic contributions, see Selective Plotting of Specific Orbitals and Atoms.

Furthermore, the colours of the lines in the density of states can be controlled by a configuration file (--config). See Custom Line Colours for more details.

### Projected Band Structures¶

sumo-bandplot can produce projected band structures, where the orbital contributions to a band are plotted. This behaviour is accessed using the --project option. The syntax for specifying which orbitals to project is as follows:

• Elements are identified using their symbol from the POSCAR

• Multiple elements are separated via commas.

• Specific orbitals can be chosen by adding the orbital after the element using a period as a separator.

• If multiple orbitals are included for a single element definition, these will be combined into a single contribution.

• If no orbitals are specified but the atomic symbol is included, then all orbitals of that element will be combined.

• Multiple definitions for the same element are allowed (e.g. each specifying different orbitals).

For example, to project the Sn s orbitals, the Sn p orbitals and a combined contribution from all the I orbitals, the command would be:

sumo-bandplot --project Sn.s,Sn.p,I


For projected plots, the band structure and the projections are interpolated to ensure the bands are smooth. The degree of interpolation can be controlled by the --interpolate-factor option. The default is 4, meaning the density of the eigenvalues and projections is quadrupled.

Multiple projection modes are supported. These are controlled by the --mode option.

RGB Mode

The default is --mode rgb. Here the line colour depends on the character of the band. Each element or orbital contributes either red, green or blue, with the corresponding line colour a mixture of all three colours. This mode only supports up to 3 element/orbitals combinations. The order of the elements/orbitals determines which colour is used for each selection.

For example, if the following command is run in the sumo/tests/data/Cs2SnI6/bandstructure directory, the output should look like:

sumo-bandplot --project Sn.s,Sn.p,I --ymin -4 --width 4


Stacked Mode

If using --mode stacked, the element or orbital contributions are drawn as a series of stacked circles. The size of the circles can be scaled using the --circle-size option. This mode supports an unlimited number of element/orbital contributions.

For example, if the following command is run in the sumo/tests/data/OsO2/bandstructure directory, the output should look like:

sumo-bandplot --project Os.d,O.p,Os.s --mode stacked --circle-size 90


It is possible to combine both the --density and --project keywords. For best results, it is advised to use a configuration file (see Custom Line Colours) to ensure the colours are consistent.

For example, using the following configuration file (stored in this example as my_colours.conf):

[I]
p = b

[Sn]
s = r
p = g


The following command, run in the sumo/tests/docs/Cs2SnI6/bandstructure folder, should output the graphic below:

sumo-bandplot  --dos ../dos/vasprun.xml.gz \
--project Sn.s,Sn.p,I.p \
--config my_colours.conf \
--ymin -4


### Questaal¶

Basic band structure plotting is supported for LMTO calculations with Questaal using lmf. (Orbital projection is not currently included.)

A structure file (site.ext), symmetry lines file (syml.ext) and band structure output file (bnds.ext) should be present in the same directory with the same ext identifier. You can then plot with Sumo:

sumo-bandplot --code questaal -f bnds.ext


The usual appearance options are supported.

## Command-Line Interface¶

bandplot is a script to produce publication-ready band structure diagrams

usage: sumo-bandplot [-h] [-f F [F ...]] [-c CODE] [-p P] [-d D] [-b]
[--project S] [--mode MODE] [--interpolate-factor N]
[--cartesian] [--circle-size S] [--ylabel YLABEL]
[--dos-label DOS_LABEL] [--dos DOS] [--elements E]
[--orbitals O] [--atoms A] [--spin SPIN]
[--scissor SCISSOR] [--total-only] [--no-total]
[--legend-cutoff C] [-g G] [--scale SCALE]
[--height HEIGHT] [--width WIDTH] [--ymin YMIN]
[--ymax YMAX] [--style STYLE [STYLE ...]]
[--no-base-style] [--config CONFIG] [--format FORMAT]
[--dpi DPI] [--font FONT]


### Named Arguments¶

-f, --filenames

one or more vasprun.xml files to plot

-c, --code

Electronic structure code (default: vasp).”questaal” also supported.

Default: “vasp”

-p, --prefix

prefix for the files generated

-d, --directory

output directory for files

-b, --band-edges

highlight the band edges with markers

Default: False

--project

select which orbitals to project onto the band structure (e.g. “Zn.s,Zn.p,O”)

--mode

mode for orbital projections (options: rgb, stacked)

Default: “rgb”

--interpolate-factor

interpolate factor for band structure projections (default: 4)

Default: 4

--cartesian

Read cartesian k-point coordinates. This is only necessary for some Questaal calculations; Vasp outputs are less ambiguous and this option will be ignored if –code=vasp.

Default: False

--circle-size

circle size for “stacked” projections (default: 150)

Default: 150

--ylabel

y-axis (i.e. energy) label/units

Default: “Energy (eV)”

--dos-label

Axis label for DOS if included

--dos

path to density of states vasprun.xml

--elements

elemental orbitals to plot (e.g. “C.s.p,O”)

--orbitals

orbitals to split into lm-decomposed contributions (e.g. “Ru.d”)

--atoms

atoms to include (e.g. “O.1.2.3,Ru.1.2.3”)

--spin

select only one spin channel for a spin-polarised calculation (options: up, 1; down, -1)

--scissor

apply scissor operator

--total-only

only plot the total density of states

Default: False

--no-total

don’t plot the total density of states

Default: True

--legend-cutoff

cut-off in % of total DOS that determines if a line is given a label (default: 3)

Default: 3

-g, --gaussian

standard deviation of DOS gaussian broadening

--scale

scaling factor for the density of states

Default: 1

--height

height of the graph

--width

width of the graph

--ymin

minimum energy on the y-axis

Default: -6.0

--ymax

maximum energy on the y-axis

Default: 6.0

--style

matplotlib style specifications

--no-base-style

prevent use of sumo base style

Default: False

--config

colour configuration file

--format

image file format (options: pdf, svg, jpg, png)

Default: “pdf”

--dpi

pixel density for image file

Default: 400

--font

font to use

Author: Alex Ganose Version: 1.0 Last updated: July 18, 2017