DynaPhoPhy is an open source (MIT License) python library for Phonon anharmonic properties from Molecular Dynamics.
DynaPhoPhy allows to calculate anharmonic phonon linewidhts and
frequency shifts using the mode descomposition technique. To do that
it uses a VASP or LAMMPS Molecular Dynamics (MD) trajectory and
projects it onto a set of harmonic phonon modes obtained by
Phonopy. Afterwards the power spectrum is calculated usign
Fourier transform or Maximum Entropy Method (MEM) and the peaks are
fitted to Lorentzian functions to extract the phonon anharmonic
Detailed documentation on how to use : Docs
Source Code: Github
The steps on high level to use DynaPhoPhy are listed below with text quoted from the docs page.
- Obtain input data by preparing Phonopy harmonic lattice dynamics calculation
For many of the features of DynaPhoPhy the phonon eigenvectors are
necessary. These eigenvectors are calculated from the harmonic phonon
force constants using phonopy. To do this calculation DynaPhoPy
requires either a phonopy FORCE_SETS or FORCE_CONSTANTS type file.
These files can be created using phonopy, just follow the instruction
in phonopy tutorial to obtain them. Keep the original POSCAR file used
in the calculation containing the unaltered unit cell. This file is
used as input for DynaPhoPy to define the unitcell.
- Prepare Molecular Dynamics (MD) calculation At the present time
DynaPhoPy implements interfaces for VASP and LAMMPS output files.
Using VASP VASP is a popular software to perform first principles calculations of solids. DynaphoPy can read the MD trajectory from
either OUTCAR or XDATCAR output files. Please, refere to VASP online
manual for detailed information to how to calculate a MD simulation.
- Execute DynaPhoPhy
dynaphopy input_file OUTCAR (VASP)
dynaphopy input_file LAMMPS.lammpstrj -ts 0.002 (LAMMPS)