Examples

The following forcefield optimization examples showcase the features of EZFF

sw-serial

Optimization of a Stillinger-Weber forcefield for the 2H-MoSe2 monolayer system against 3 objectives – Lattice constant (a), Elastic modulus (\(C_{11}\)) and Phonon dispersion

Features demonstrated in this example

  1. Reading-in phonon dispersion from GULP and VASP data files
  2. Calculating error between phonon dispersions
  3. Calculating error between computed and ground-truth phonon dispersions
  4. Reading-in elastic modulus tensor from GULP run

sw-parallel

Parallel optimization of a Stillinger-Weber forcefield for the 1T’ monolayer system against 6 objectives – Two lattice constants (a and b), One elastic modulus (\(C_{11}\)) and Three phonon dispersion curves (one each for compressed, relaxed and expanded crystals)

Features demonstrated in this example

  1. All features from sw-serial
  2. Spawning and using MPI pools for optimization
  3. Non-uniform weighting schemes for calculating phonon dispersion errors

rxff-serial

Optimization of ReaxFF forcefield for a thio-ketone monomer against 2 objectives – Dissociation energy of the C-S bond and C-S vibrational frequency

Features demonstrated in this example

  1. Using QChem interface to read-in QM energies
  2. Using GULP interface to perform single-point calculations and read-in energy
  3. Using utils.reaxff to construct GULP-compatible reaxff library files

rxff-parallel

Parallel optimization of ReaxFF forcefield for a thio-ketone monomer against 2 objectives – Dissociation energy of the C-S bond and C-S vibrational frequency

Features demonstrated in this example

  1. All features from rxff-serial
  2. Using utils.reaxff methods for generating forcefields templates and variable range files