gpaw-tools

Introduction

gpaw-tools is a bunch for python scripts for easy performing of GPAW calculations. It is mostly written for new DFT users who are running codes in their own PCs or on small group clusters.

gpaw-tools have:

1. A force-field quick optimization script quickoptimization.py for preliminary calculations using ASAP3/OpenKIM potentials.
2. ciftoase.py script for transform CIF files to ASE's own Atoms object.
3. To choose better cut off energy, lattice parameter and k points, there are 3 scripts called optimize_cutoff.py, optimize_latticeparam.py and optimize_kpoints.py.
4. And, the main solver script gpawsolver.py which can be run in PW or LCAO mode. It can do strain minimization, can use several different XCs, can do spin-polarized calculations, can calculate, draw and save tidily DOS and band structures, can calculate and save all-electron densities and can calculate optical properties in a very simple and organized way.

Usage

Installation

When you download gpaw-tools-main from GitHub and extract it to a folder you will have a folder structure as:

gpaw-tools-main/
└── benchmarks/
│   └── simple_benchmark_2021.py
├── examples/
├── optimizations/
│   ├── ciftoase.py
│   ├── optimize_cutoff.py
│   ├── optimize_kpoints.py
│   └── optimize_latticeparam.py
├── quick_optimization/
|   └── quickoptimize.py
├── gui_files/
└── gpawsolve.py
└── gg.py
└── config.py

To make the gpawsolve.py and gg.py as system-wide commands, user must include the gpaw-tools-main folder to the $PATH variable in the .bashrc file. In case of user downloaded and extracted the gpaw-tools-main file to user's home directory, and to make the change permanent, user must need to define the $PATH variable in the shell configuration file .bashrc as

export PATH="/home/username/gpaw-tools-main:$PATH"

also you may need to give execute rights to gpawsolve.py and gg.py to execute these scripts as a command

cd /home/username/gpaw-tools-main
chmod +x gpawsolve.py gg.py

gpawsolve.py

This is the main script for easy and ordered PW/LCAO Calculations with ASE/GPAW. It can run as a stand-alone script or as a command.

As a command:

Command line usage: gpawsolve.py -v -o -r -d -c <configfile.py> -h -i <inputfile.cif>

Argument list:

-i, --input      : Use input CIF file
-c, --config     : Use configuration file in the main directory for parameters (config.py) If you do not
                   use this argument, parameters will be taken from the related lines of gpawsolve.py
-o, --outdir     : Save everything to a output directory with naming /inputfile. 
                   If there is no input file given and Atoms object is used in gpawsolve.py file 
                   then the directory name will be /gpawsolve. If you change gpawsolve.py name to 
                   anyname.py then the directory name will be /anyname
-h --help        : Help
-d --drawfigures : Draws DOS and band structure figures at the end of calculation.
-r --restart     : Passing ground calculations and continue with the next required calculation.
-v --version     : Version information of running code and the latest stable code. Also gives download link.

You can put ASE Atoms object in to your config file and therefore can use it like an input file. As an example please note the example at: examples\Bulk-aluminum folder.

As a stand alone script

• Change the parameters from related lines for each simulation OR change config.py once and use -c argument.
• If you want to use CIF files for structure, use -i argument like gpawsolve.py -i structurefile.cif.
• If you want to use ASE atoms method for structure, just copy/paste your Atoms info into the part mentioned with "Bulk Structure".
• If you have CIF file but want to use Atoms method you can use CIF-to-ASE/ciftoase.py to convert your CIF files to ASE Atoms.
• If you use Atoms method, change the name of gpawsolve.py to your simulation name like graphene7x7-Fe-onsite32.py. The naming will be used for naming of all output/result files.
• If you use CIF file as an input, name of the input file will be used for naming of all output/result files.
• Performance note: When you want to use gpawsolve.py as a script, you can copy gpawsolve.py to your working folder where your config file and input file are ready. You must rename gpawsolve.py to something else like gpawsolve1.py or gs-graphene.py, something you like and then you can now run gpaw -P<core> python gpawsolve1.py <args> type command. Initializing with gpaw command in your system will give you better parallel computing, therefore shorter computation times. Initialization with gpaw can not be done when gpawsolve.py is used as command, because of the structure of initialization of Gpaw, as we know. If you know a solution from the point of view of gpaw-tools, please use issues to discuss or pull request for a solution.

How to run?

Change <core_number> with core numbers/threads to use. For getting a maximum performance from your PC you can use total number of cores(or threads) - 1. or total RAM/2Gb as a <core_number>

Usage: For AMD CPUs or using Intel CPUs without hyperthreading: $ mpirun -np <core_number> gpawsolve.py <args>

For using all threads provided by Intel Hyperthreading technology $ mpirun --use-hwthread-cpus -np <core_number> gpawsolve.py <args>

Calculation selector

Method	Strain_minimization	Different XCs	Spin polarized	DOS	DFT+U	Band	Electron Density	Optical
PW	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
PW-G0W0	Yes	Yes	No	No	No	Yes	No	No
EXX*	Yes (with PBE)	No	No	No	No	No	No	No
LCAO	No	No	No	Yes	Yes	Yes	Yes	No
*: Just some ground state energy calculations for PBE0 and HSE06.

gg.py

Basic DFT calculations can be done graphically with the script gg.py. This script is behaving as a GUI to run gpawsolve.py script. To execute the GUI, type simply: gg.py

quick_optimize/quickoptimize.py

Inter-atomic potentials are useful tool to perform a quick geometric optimization of the studied system before starting a precise DFT calculation. The quickoptimize.py script is written for geometric optimizations with inter-atomic potentials. The bulk configuration of atoms can be provided by the user in the script as an ASE Atoms object or given as an argument for the CIF file. A general potential is given for any calculation. However, user can provide the necessary OpenKIM potentialby changing the related line in the script.

Mainly, quickoptimize.py is not related to GPAW. However it is dependent to ASAP3/OpenKIM and Kimpy. Therefore, the user must install necessary libraries before using the script:

pip install --upgrade --user ase asap3
sudo add-apt-repository ppa:openkim/latest
sudo apt-get update
sudo apt-get install libkim-api-dev openkim-models libkim-api2 pkg-config
pip3 install kimpy

The script can be called as: from the command line in the script itself:

python quickoptimize.py                   (if the user wants to provide structure as ASE Atoms object)
python quickoptimize.py <inputfile.cif>   (if the user wants to provide structure as a CIF file

optimizations/ciftoase.py

For quickoptimize.py or other optimization scripts, user may need to give ASE Atoms object instead of using a CIF file. This script changes a CIF file information to ASE Atoms object. Because there is a problem in the read method of ASE.io, sometimes it can give a double number of atoms. If the user lives this kind of problem, there is a setting inside the script. User can run the script like:

python ciftoase.py <inputfile.cif>

Result will be printed to screen and will be saved as inputfile.py in the same folder.

optimizations/optimize_cutoff (and kpoints)(and latticeparam).py

Users must provide ASE Atoms object and simply insert the object inside these scripts. With the scripts, the user can do convergence tests for cut-off energy, k-points and can calculate the energy dependent lattice parameter values. These codes are mainly based on Prof. J. Kortus, R. Wirnata's Electr. Structure & Properties of Solids course notes and GPAW's tutorials. Scripts can easily called with MPI as:

gpaw -P <core_number> python optimize_cutoff.py
gpaw -P <core_number> python optimize_kpoints.py
gpaw -P <core_number> python optimize_latticeparam.py

benchmarks/

GPAW has many test scripts for many cases. However, new users may need something easy to run and compare. Some very easy single file test scripts will be listed here with some hardware benchmark information. Your timings are always welcomed.

examples/

There are some example calculations given with different usage scenarios. Please send us more calculations to include in this folder.

Release notes

Release notes are listed at here.

Licensing

This project is licensed under the terms of the MIT license.