Qball (also known as qb@ll) is a first-principles molecular dynamics code that is used to compute the electronic structure of atoms, molecules, solids, and liquids within the Density Functional Theory (DFT) formalism. It is a fork of the Qbox code by Francois Gygi.
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README.md

Qball

Installing

To compile Qbox:

  1. Generate the configure script (you need autoconf and automake).
autoreconf -i
  1. Now you need to determine how to run the configure script. Since Qball depends on some non-standard libraries you might need to set some environment variables and to add some flags to tell qball where to find those libraries.
Environment variable Description Note
CC C compiler Default is mpicc
CXX C++ compiler Default is mpic++
FC Fortran compiler Default is mpif90. Used only to detect Fortran libraries.
CFLAGS C compiler flags
CXXFLAGS C++ compiler flags
FCFLAGS Fortran compiler flags Used only to detect Fortran libraries.
LDFLAGS Flags to add to the linker
LIBS Extra libs add to linking
LIBS_BLAS Compilation flags to add the blas library
Flag Value Note
--prefix= installation directory default is /usr/local
--with-fftw3-prefix= path where fftw3 is installed
--with-fftw2-prefix= path where fftw2 is installed
--with-essl-prefix= path where the IBM ESSL library is installed
--with-blas= path where the Blas library file is located you can also use LIBS_BLAS
--with-lapack= path where the lapack library file is located
--with-blacs= path where the blacs library file is located you can also pass the location of scalapack
--with-scalapack= path where the scalapack file is located

For example, for a Blue Gene/Q system, you configure script might look something like this:

QBALLPREFIX=/usr/local/
QBALLDEPS=$QBALLPREFIX/dependencies/
export CC=mpixlc_r
export CXX=mpixlcxx_r
export FC=mpixlf95_r
export LIBS_BLAS="-L/usr/local/tools/essl/5.1/lib/ -lesslsmpbg"
export LIBS_BLACS="-lmpiblacs"
export LDFLAGS="-qsmp=omp"
export CFLAGS="-O3 -qsmp=omp -qarch=qp -qtune=qp"
export CXXFLAGS="$CFLAGS -qlanglvl=extended0x"
export FCFLAGS=$CFLAGS" -qxlf90=autodealloc -qessl -I$HOME/$xarch/fftw-3.3.4/include"
./configure --with-essl-prefix=/usr/local/tools/essl/5.1/ \
  --with-lapack=$QBALLDEPS/lib/liblapack.a --with-blacs=$QBALLDEPS/lib/libscalapack.a --prefix=$QBALLPREFIX
  1. Run the configure script with the necessary flags:
./configure --prefix=... 
  1. Now we are ready to build the code:

    make
    make install
    

Contact Erik Draeger (draeger1@llnl.gov) or Xavier Andrade (xavier@llnl.gov) with any questions or problems.

Running

To run Qball, one needs an input file (.i), a coordinate file (.sys) and pseudopotential file(s) (.xml). Input examples can be found in the examples/ directory.

The input file can be specified either as an argument or as stdin to qball, e.g.

srun -n 16384 qball gold.N992.i > gold.N992.out

srun -n 64 qball < test.i > test.out

Release

Qball is licensed under the terms of the GPL v3 License.

LLNL-CODE-635376