DFTB+ installation#

There are two ways the install DFTB+:

  1. via conda-forge (easier to setup but less optimized)

  2. via compilation

In this documentation, the compilation method will be discussed in detail.

Compilation method#

The DFTB+ executable can be compiled with 4 parallelism types:

  1. Serial (non-parallelized)

  2. OpenMP (parallelize via threads, shared memory)

  3. MPI (parallelize via mpi, distributed memory)

  4. OpenMP-MPI hybrid (parallelize via thread and mpi, not discussed)

For simplicity and stability OpenMP parallelism will be used. This is also the default parallelism of DFTB+

What to use: Serial, OpenMP or MPI

Serial is just good for testing.

OpenMP seems good for relatively small systems that uses a single node.

MPI may be better for larger systems that requires more than a single node. For small systems, MPI takes longer than OpenMP.

Between OpenMP and MPI, OpenMP parallization is the default way of using DFTB+. Its usage is also heavily documented. MPI, on the otherhand, is not. The non-MPI version supports more excited state methods, while the MPI version has better parallelism for many tasks.

Load compilers and python environment#

# Load compilers
module load cmake/3.18.3
module load intel/2020.2.254
module load intelmpi/2020.2.254
module load python/3.8

# Load python environment
source activate tutorial

Download and use the DFTB+ installer#

We will use the DFTB+ version 22.1 (Other releases are available here)

We first create a tutorial_files directory in $HOME to keep our files clean.

1. Prepare the installation directory#

# Download source files
tutordir=~/tutorial_files
mkdir -p $tutordir/apps && cd $tutordir/apps

2. Install using the automation script#

Download the installer. There are two installers available: (a) OpenMP version and (b) MPI version. Feel free to choose any, but here we use OpenMP version.

wget https://raw.githubusercontent.com/kimrojas/gofee-book/master/book/files/install-dftb-openmp.py
chmod +x install-dftb-openmp.py
./install-dftb-openmp.py

Want the MPI version?

In case you want the MPI version, it is available here: install-dftb-mpi.py

It works and has been tested very slightly. Hard to use.

Declare the path#

The install-dftb-mpi.py installer script will return an advice on how to properly declare the PATHing of DFTB+. In my case, it looks like this:

SHOWING IMPORTANT PATHS
BASE DIRECTORY = /home/krojas/tutorial_files/apps/dftbplus-22.1-OpenMP/_install
- - - - -
add to PATH            : /home/krojas/tutorial_files/apps/dftbplus-22.1-OpenMP/_install/bin
add to LD_LIBRARY_PATH : /home/krojas/tutorial_files/apps/dftbplus-22.1-OpenMP/_install/lib64
add to PYTHONPATH      : /home/krojas/tutorial_files/apps/dftbplus-22.1-OpenMP/_install/lib/python3.8/site-packages/pythonapi-0.1-py3.8.egg
set variable DFTB_LIB  :  /home/krojas/tutorial_files/apps/dftbplus-22.1-OpenMP/_install/lib64
- - - - -
SLAKOS FILES
https://dftb.org/parameters/download/all-sk-files

There are a few ways to declare this: (a) Update startup script (bashrc or bash_profile), (b) custom module environment, or (c) exporter script. For simplicity, let’s create an exporter script.

Create an activate_dftb.sh file:

#!/bin/bash
installdir=/home/krojas/tutorial_files/apps/dftbplus-22.1-OpenMP/_install

export PATH=${installdir}/bin:$PATH
export LD_LIBRARY_PATH=${installdir}/lib64:$LD_LIBRARY_PATH
export PYTHONPATH=${installdir}/lib/python3.8/site-packages/pythonapi-0.1-py3.8.egg:$PYTHONPATH
export DFTB_LIB=${installdir}/lib64

From now on, we just use this script to activate dftb+,

source ~/tutorial_files/apps/activate_dftb.sh

INSTALLATION COMPLETE

Conda method (a pre-compiled version)#

A pre-compiled DFTB+ executable is available in conda-forge via conda installation.

It can be simply downloaded by

conda install -n tutorial -c conda-forge 'dftbplus=*=mpi_openmpi_*' dftbplus-tools dftbplus-python

INSTALLATION COMPLETE