MCEND

MCEND (multi-configuration electron-nuclear dynamics) is a quantum dynamics code for simultaneous propagation of electrons and nuclei, written in Fortran90.

Requirements

MCEND requires Blas, Lapack and FFTW3 libraries; the tools require python3 and numpy, plus additional python libraries. The documentation requires doxygen. You will need a Fortran compiler to compile the source code. Intel Fortran is recommended as the resulting binary is computationally more efficient.

On Ubuntu, for an Intel Fortran version of 2023.2.0: sudo apt-get install intel-oneapi-compiler-fortran-2023.2.0 intel-oneapi-mkl-2023.2.0 libfftw3-dev On MacOS, install the intel oneapi base and hpc kit. Also, you need the xcode command line tools. Install fftw3 using brew install fftw3 To use gfortran, install it using brew install gfortran Compilation with ifort or gfortran is then possible using the make classic or make gfortran commands as described below.\

Compilation

To compile the source code, type make in the MCEND directory.

There are also different options available: Compile with Intel classic ifort compiler make classic Compile with gnu Fortran make gfortran All of these can also be used with options for debugging and no optimization (otherwise, -O3 optimization is used). Just combine the compiler option with the debug option, for example for intel classic: make classic_debug Alternatively, make debug (for ifx) and make debug_gfortran (for gfortran) are available. The source code compiles and runs on linux and MacOS, it has not been tested on Windows.

MCEND basis library

In order to run MCEND, you need to install the basis library. Either clone the library directly into a directory of your choice, or use it through the provided git submodule. In order to check out the files of the submodule, either clone MCEND directly using the --recursive flag, or type git submodule update --init --recursive in your terminal within the MCEND folder. You should then find all the basis set files inside MCEND-library/basis_library/.

To provide the directory of the basis set files, you can either set absolute or relative paths for the intpath input parameter in the input file. Or, for ease of use, set an MCEND_BASIS_LIBRARY environment variable to point to the MCEND basis set library. For example, in bash: export MCEND_BASIS_LIBRARY=/User/username/MCEND-libary/basis_library where you need to adapt the path accordingly. Then the intpath variable only requires the name of the basis set, for example intpath = integrals_H2-g4bf27.

Developer's documentation

The source code documentation can be build on your local machine using cd doc doxygen Doxyfile Open the resulting doc/html/index.html with your browser.