MILADY potentials in Lammps

In order to use MILADY potentials with Lammps you should compile Lammps``with ``Milady library. The next section Using briefly summarizes how to employ in Lammps our potentials while the section Installing details the full Lammps + MILADY installation.

Using MILADY potentials

Running Lammps with MiLaDy potentials is easy: set in Lammps input file the pair_style as milady and indicate the name of your potential file:

pair_style milady
pair_coeff * * Fe_LML.pot Fe

For many elements you should just provide the elements for which your elements where designed. E.g. for one potential designed for a TaTiVW HEA the pair_coeff line is as follow:

pair_coeff * * hea.pot Ta Ti V W

The ready-to-use input files can be found in Examples of this repository

Installing Lammps and MILADY

Here we provide the steps for building Lammps with MILADY patch will call this as milady_lammps.

Note

milady_lammps installation is similar to Lammps regular installation for which the library ml-milady is on. So far, for the users, which have experience with Lammps installation they can go directly to milady_lammps part.

The current version of milady_lammps requires:

  • Fortran compiler: gfortran OR ifort

  • C++ compiler: g++

  • MKL library from Intel (for this installation) or any other Lapack/ScaLapack distribution.

We have tested installations with following versions:

g++        (version >= 9.0.0)
gfortran   (version >= 9.0.0)
ifort      (version >= 2018.0.0)
MKL        (version >= 2018.0.0) with gfortran support

We describe here the way that we use and we know that it works. If you know a better precedure, we are happy to learn about your experience. You can to update the present documentation.

  1. Clone our repository of milady_lammps:

git clone --recursive git@github.com:tomswinburne/milady_lammps.git milady_lammps.git

  1. turn on MILADY library in Lammps:

cd milady_lammps.git/src
make yes-ml-milady

3. Choose the compilator for milady_lammps: intel or gfortran. Note that there is no restriction in the choice that you have for the compilation of Lammps (we use default parameters and g++ compiler). Below, we provide the 2-step example using Intel Fortran ifort. The case of gfortran is similar.

3a. Edit the appropiate Makefile.lammps.ifort for your architecture. milady_lammps library uses MKL and some other Intel libraries from Intel Fortran compiler. You need to localize the root directory for MKL and intel64 libraries. We use oneAPI Intel free distribution. Here are our choices:

MKLROOT=/opt/intel/oneapi/mkl/latest/
LIBCOMP=/opt/intel/oneapi/compiler/latest/linux/compiler/lib/intel64/

The paths will be similar for any older distribution of MKL and Intel Fortran, such as Intel Composer, Intel Parallel Studio, etc. If you have doubts: write us . We are happy to help you !!!!

Note

If this is too painful, for you we provide some examples of Makefile.lammps.ifort on various computers. Here you can found an Makefile.lammps.ifort for HPC Marconi , TGCC Irene and some personal computer . After download please copy that file in lib/milady/Makefile.lammps.ifort

3b. Compile milady library in milady_lammps:

cd milady_lammps.git/lib/milady
make -f Makefile.mpi_ifort  clean
make -f Makefile.mpi_ifort

  1. milady_lammps final compilation …. ouufff:

cd milady_lammps.git/src
make mpi

Warning

Sometime the default main makefile of Lammps, i.e. Lammps/src/MAKE/Makefile.mpi, is somehow different from platform to platform. If this last point has some problems, it means that you have some inconsistencies in the Lammps compilation. Try with one of the following Makefile.mpi file, which we use for some platfroms, such as Marconi , TGCC Irene or some personal computer .

That’s it! We know … compilations are painful!

Note

IMPORTANT: Many thanks to users that have reported some typos, errors in Makefile. In particular many thanks to Marie Landeiro Dos Reis, Antoine Kraych and Jan Wróbel!