.. index:: QUIP
.. _QUIP:

QUIP
====

Description
-----------

The QUIP package is a collection of software tools to carry out molecular dynamics simulations. It implements a variety of interatomic potentials and tight binding quantum mechanics, and is also able to call external packages, and serve as plugins to other software such as LAMMPS, VASP and also the python framework ASE. Various hybrid combinations are also supported in the style of QM/MM, with a particular focus on materials systems such as metals and semiconductors.

For more details, see the `online documentation. <http://libatoms.github.io/QUIP>`_

User instructions
-----------------

QUIP is available via the modules system.  To add it to your environment run:

.. code-block:: bash

    $ module load quip/2017.08.24

.. note::

    The module loads both the main executable and the python scripts and wrappers and so needs the following modules: gcc mkl openmpi ase numpy scipy.

Source
------

https://github.com/libAtoms/QUIP

License
-------

Mostly GNU General Public License, version 2, with some portions in the public domain.

Admin notes
-----------

Mainly, follow the "Compilation Instructions" section on the github page linked above.

.. code-block:: bash

    $ ml intel mkl openmpi python/2.7.13 ase
    $ export QUIP_ARCH=linux_x86_64_ifort_icc_mpi
    $ export QUIP_INSTALLDIR=/common/debian/9.1/MPI/intel/2017.4/openmpi/2.1/quip/quip-2017.08.24/bin
    $ make config

In the dialogues that follow, choose lapack and blas as ``-lmkl_intel_lp64 -lmkl_sequential -lmkl_core -lm``, and enable vasp, tight_binding, LotF, ONIOM and local_E_mix, and disable preconditioned minimization support.

.. code-block:: bash

    $ make
    $ make quippy
    $ make libquip
    $ make test # seems to fail for intel
    $ mkdir -p /common/debian/9.1/MPI/intel/2017.4/openmpi/2.1/quip/quip-2017.08.24/bin
    $ make install

Note, the various ``.a`` files from ``build/$QUIP_ARCH/lib`` directory and the quippy build python scripts and lib directory need to be put in place manually.

As intel tests failed, a gcc version was also compiled. In this case the BLAS and LAPACK linking options are ``-lmkl_gf_lp64 -lmkl_sequential -lmkl_core -lm`` and the config options are as in the case of intel except preconditioned minimization support can be enabled. Everything else is as in the case of the intel compiler.

Note 1: as there is no clear versioning, I take the iso date that I cloned the git repo.

Note 2: the version of openmpi used will have to have been compiled with the ``--disable-dlopen`` option set at the configure stage for quippy to work. This is the case for all the openmpi compilations on our system.