euphonic-dos¶
The euphonic-dos
program can be used to plot density of states,
partial density of states, and/or neutron-weighted density of states.
It can use pre-calculated frequencies, or use force constants to
generate frequencies and DOS over a Monkhorst-Pack grid. For example,
to plot DOS from a CASTEP .phonon
file in units of 1/cm, run:
euphonic-dos --energy-unit 1/cm quartz-554-grid.phonon
Or, to plot coherent neutron-weighted DOS from CASTEP force constants in a
.castep_bin
file on a 15x15x12 grid with broadening, run:
euphonic-dos --weighting coherent-dos --grid 15 15 12 --energy-broadening 1.5 quartz.castep_bin
To see all the command line options, run:
euphonic-dos -h
You can also see the available command line options below
Command Line Options¶
Plots a DOS from the file provided. If a force constants file is provided, a DOS is generated on the Monkhorst-Pack grid specified by the grid (or grid-spacing) argument.
usage: euphonic-dos [-h] [--asr [{reciprocal,realspace}]]
[--dipole-parameter DIPOLE_PARAMETER]
[--use-c | --disable-c] [--n-threads N_THREADS]
[--pdos [PDOS [PDOS ...]]]
[--weighting {dos,coherent-dos,incoherent-dos,coherent-plus-incoherent-dos}]
[--grid GRID GRID GRID | --grid-spacing GRID_SPACING]
[-s SAVE_TO] [--title TITLE] [--x-label X_LABEL]
[--y-label Y_LABEL] [--e-min E_MIN] [--e-max E_MAX]
[--energy-unit ENERGY_UNIT] [--ebins EBINS] [--adaptive]
[--energy-broadening ENERGY_BROADENING]
[--shape [{gauss,lorentz}]] [--length-unit LENGTH_UNIT]
filename
File I/O arguments¶
- filename
Phonon data file. This should contain force constants or phonon mode data. Force constants formats: .yaml, force_constants.hdf5 (Phonopy); .castep_bin , .check (Castep); .json (Euphonic). Phonon mode data formats: {band,qpoints,mesh}.{hdf5,yaml} (Phonopy); .phonon (Castep); .json (Euphonic)
q-point sampling arguments¶
- --grid
Defines a Monkhorst-Pack grid.
- --grid-spacing
q-point spacing of Monkhorst-Pack grid.
Default: 0.1
- --length-unit
Length units; these will be inverted to obtain units of distance between q-points (e.g. “bohr” for bohr^-1).
Default: “angstrom”
energy/frequency arguments¶
- --e-min
Energy range minimum in ENERGY_UNIT
- --e-max
Energy range maximum in ENERGY_UNIT
- --energy-unit, -u
Energy units
Default: “meV”
- --ebins
Number of energy bins
Default: 200
- --adaptive
Use adaptive broadening on the energy axis to broaden based on phonon mode widths, rather than using fixed width broadening
Default: False
- --energy-broadening, --eb
If using fixed width broadening, the FWHM of broadening on energy axis in ENERGY_UNIT (no broadening if unspecified). If using adaptive broadening, this is a scale factor multiplying the mode widths (no scale factor applied if unspecified).
- --shape
Possible choices: gauss, lorentz
The broadening shape
Default: “gauss”
Force constants interpolation arguments¶
- --asr
Possible choices: reciprocal, realspace
Apply an acoustic-sum-rule (ASR) correction to the data: “realspace” applies the correction to the force constant matrix in real space. “reciprocal” applies the correction to the dynamical matrix at each q-point.
- --dipole-parameter
Set the cutoff in real/reciprocal space for the dipole Ewald sum; higher values use more reciprocal terms. If tuned correctly this can result in performance improvements. See euphonic-optimise-dipole-parameter program for help on choosing a good DIPOLE_PARAMETER.
Default: 1.0
Property-calculation arguments¶
- --pdos
Plot PDOS. With –pdos, per-species PDOS will be plotted alongside total DOS. A subset of species can also be selected by adding more arguments e.g. –pdos Si O
- --weighting, -w
Possible choices: dos, coherent-dos, incoherent-dos, coherent-plus-incoherent-dos
Type of DOS to plot: DOS, coherent neutron-weighted DOS, incoherent neutron-weighted DOS or total (coherent + incoherent) neutron-weighted DOS
Default: “dos”
Plotting arguments¶
- -s, --save-to
Save resulting plot to a file with this name
- --title
Plot title
Default: “”
- --x-label
Plot x-axis label
- --y-label
Plot y-axis label