A multipurpose FORTRAN2003 and MPI suite of codes for the simulation of quantum spin dynamics at the atomistic level. The code is developed to readily interface with electronic structure codes and makes it possible to predict spin decoherence and spin-phonon relaxation fully ab initio.

MolForge: a multipurpose FORTRAN2003 and MPI suite of codes for the simulation of quantum spin dynamics at the atomistic level.

Copyright (c) 2023 Trinity College Dublin

Developed by Alessandro Lunghi, School of Physics, AMBER and CRANN Institute, Trinity College, Dublin 2, Ireland

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see https://www.gnu.org/licenses/.

When using MolForge or any of its components, please always cite:

• Toward exact predictions of spin-phonon relaxation times: An ab initio implementation of open quantum system theory, Science Advances 8(31), eabn7889, 2022

Additional works that contributed towards the formalism implemented in MolForge are:

• How do phonons relax molecular spins? Science Advances, 5 (9), eaax7163, 2019

• Electronic spin-spin decoherence contribution in molecular qubits by quantum unitary spin dynamics, Journal of Magnetism and Magnetic Materials 487, 165325, 2019

• The limit of spin lifetime in solid-state electronic spins, The Journal of Physical Chemistry Letters, 11 (15), 6273-6278, 2020

• Multiple spin-phonon relaxation pathways in a Kramer single-ion magnet, The Journal of Chemical Physics 153 (17), 174113, 2020

Molforge is known to compile on Linux machines with GNU compilers(v8.2.0) and openmpi(3.1.2).

MolForge depends on the linear algebra routines Lapack (v3.8.0), Blas(v3.8.0), and Scalapack(2.1.0).

The following variables in the main Makefile might need to be set

export INC_DIR = "path to libraries include files"

export LIB_DIR = "path to libraries files"

export LIBS = -lscalapack -llapack -lblas

export INC_FLAG = -I$(INC_DIR)

export LINK_FLAG = -L$(LIB_DIR)

To compile and link MolForge and its programs, it is necessary to install the command make. The available make instances are: all, libMolForge, Spiral, Phondy, Tools, clean, clean_MolForge, clean_Spiral, clean_PhonDy, clean_Tools.

To compile all codes in one go:

cd MolForge/

make all

After successful installation, the folders libs/ and bin/ should be present in the molforge main directory. The library libMolForge will be build statically and move to libs/. All the executables will be move to bin/.