Quantum Espresso Preparation#

This guide is here to help you prepare Quantum Espresso Calculations to be used with pyprocar.

Required files : bands.in, kpdos.in, pdos.in,scf.in, atomic_proj.xml
flag : code=’qe’

Quantum Espresso v6.5+ is supported.

Preparing Calculations#

To use Pyprocar with QE, one has to run various calculations in independent directories. Here, we will show examples for the different calculations

Band Structure#

Create directory called bands.
Run pw.x on your scf.in file.
Run pw.x on your bands.in file. (Read kpoints section on how to add labels)
Run projwfc.x on your kpdos.in file (Make sure kresolveddos=.true.).
Make sure to copy the atomic_proj.xml file that is found in the .save directory into the main directory
Run pyprocar.bandsplot(dirname = ‘bands’ ,mode = ‘plain’, code = ‘qe’)

Density of States#

Create directory called dos.
Run pw.x on your scf.in file.
Run pw.x on your nscf.in file.
Run projwfc.x on your pdos.in file (Make sure kresolveddos=.false.).
Make sure to copy the atomic_proj.xml file that is found in the .save directory into the main directory
Run pyprocar.dosplot(dirname = ‘bands’ ,mode = ‘plain’, code = ‘qe’)

Band Structure and Density of States#

Run the band structure and dos calculation as stated above
Run pyprocar.bandsdosplot(bands_dirname = ‘bands’, dos_dirname = ‘dos’, bands_mode = ‘plain’, dos_mode = ‘plain’, code = ‘qe’)

Fermi#

Create directory called fermi.
Run pw.x on your scf.in file.
Run pw.x on your nscf.in file.
Run projwfc.x on your kpdos.in file (Make sure kresolveddos=.true.).
Make sure to copy the atomic_proj.xml file that is found in the .save directory into the main directory
Run pyprocar.fermi3D

K-Points Format#

The \(k\)-path can be specified in bands.in which is used for the band structure calculation as one of the following:

K_POINTS {crystal_b}
8
0000000000       0.0000000000       0.0000000000       30 !G
5000000000       0.0000000000       0.5000000000       30 !X
6250000000       0.2500000000       0.6250000000       1  !U
3750000000       0.3750000000       0.7500000000       30 !K
0000000000       0.0000000000       0.0000000000       30 !G
5000000000       0.5000000000       0.5000000000       30 !L
5000000000       0.2500000000       0.7500000000       30 !W
5000000000       0.0000000000       0.5000000000       30 !X

Where the one occurs is at the place of a discontinuity.

Explicit:

K_POINTS {crystal}
269
    0.0000000000       0.0000000000       0.0000000000      1.0 !G
    0.0083333333       0.0000000000       0.0083333333      1.0
    0.0166666667       0.0000000000       0.0166666667      1.0
    0.0250000000       0.0000000000       0.0250000000      1.0
    0.0333333333       0.0000000000       0.0333333333      1.0
    0.0416666667       0.0000000000       0.0416666667      1.0
    .
    .
    .
    0.4916666667       0.0000000000       0.4916666667      1.0
    0.5000000000       0.0000000000       0.5000000000      1.0 !X
    0.5062500000       0.0125000000       0.5062500000      1.0
    .
    .
    .
    0.6125000000       0.2250000000       0.6125000000      1.0
    0.6187500000       0.2375000000       0.6187500000      1.0
    0.6250000000       0.2500000000       0.6250000000      1.0 !U
    0.3750000000       0.3750000000       0.7500000000      1.0 !K
    0.3691406250       0.3691406250       0.7382812500      1.0
    0.3632812500       0.3632812500       0.7265625000      1.0
    0.3574218750       0.3574218750       0.7148437500      1.0
    .
    .
    .
    0.0058593750       0.0058593750       0.0117187500      1.0
    0.0000000000       0.0000000000       0.0000000000      1.0 !G

Explicitly listing kpoints as ‘’!kpoint” is important for labels

Magnetic Calculations#

Magnetic calculations follow the same steps as above, but it requires additional parameters

Colinear-Spin

To perform Colinear-Spin calculations, nspin = 2 and starting_magnetization must be set in the input of the PW files (scf.in,nscf.in,bands.in,)

Non-colinear-Spin

Non-colinear-Spin-Spin calculations take some additional steps as it requires a branch of Quantum Espresso code to print out the spin projections.

Follow these steps to install the qe branch:

git clone git@gitlab.com:pietrodelugas/q-e.git
cd q-e
git checkout new_proj
Install package.
Set PATH to the bin directory in side q-e

Now, to perform the calculations set noncolin = .true. and lspinorb = .true. in the input of the PW input files (scf.in,nscf.in,bands.in,).

Also, set savesigma=.true. in the PROJWFC input files (kpdos.in,pdos.in).