libvdwxc - A library for vdW-DF exchange-correlation functionals

This module allows the description of long-range electronic interactions between atoms and molecules.

Purpose of Module

libvdwxc is a general library for evaluating energy and potential for exchange-correlation (XC) functionals from the vdW-DF family that can be used with various density functional theory (DFT) codes. This work was inspired by the success of libXC, a library for local and semilocal XC functionals. At the moment, libvdwxc provides access to the vdW-DF1, vdW-DF2, and vdW-CX functionals. It provides interfaces for GPAW and Octopus. The library has been tested with respect to the S22 test set, various bulk properties of metals and semiconductors, and surface energies.

In a previous effort Marques et al. created a C library called LibXC. This library consists of 400 different local and semi-local functionals, and it is linked by 20 different codes. In other words, when using this library, scientists have thousands different functional and code combinations to choose from. The publication process of a functional becomes easier, because it needs just to be added into one place. In a similar spirit, libvdwxc is intended as a library that enables calculations of a particular family of functionals, which cannot be readily added to LibXC.

Background Information

All relevant information about libvdwxc, as well as downloadable packages, can be found at:

Building and Testing

libvdwxc provides an Autotools-based build system. Its build procedure is relatively straightforward:

cd libvdvwxc-x.y.x mkdir my_build_dir cd my_build_dir ../configure –prefix=/my/install/dir make make check make install

where x.y.z is the version of libvdwxc you want to install, my_build_dir is the build directory where you will compile the library, and /my/install/dir is the absolute path where you want to install it.

Build parameters can be adjusted by providing options to the configure script. To get a list of available options, you can use the --help option of the configure script, e.g. run:

./configure –help

from the top source directory of libvdwxc, or:

../configure –help

from your build directory.

For more information about the Autotools, please consult the Autotools Mythbuster.

Source Code

The source code of libvdwxc is hosted on Gitlab.