Other built-in calculators

TIP3P

class ase.calculators.tip3p.TIP3P(rc=5.0, width=1.0)[source]

TIP3P potential.

rc: float

Cutoff radius for Coulomb part.

width: float

Width for cutoff function for Coulomb part.

TIP4P

class ase.calculators.tip4p.TIP4P(rc=7.0, width=1.0)[source]

TIP4P potential for water.

http://dx.doi.org/10.1063/1.445869

Requires an atoms object of OHH,OHH, … sequence Correct TIP4P charges and LJ parameters set automatically.

Virtual interaction sites implemented in the following scheme: Original atoms object has no virtual sites. When energy/forces are requested:

  • virtual sites added to temporary xatoms object

  • energy / forces calculated

  • forces redistributed from virtual sites to actual atoms object

This means you do not get into trouble when propagating your system with MD while having to skip / account for massless virtual sites.

This also means that if using for QM/MM MD with GPAW, the EmbedTIP4P class must be used.

Lennard-Jones

class ase.calculators.lj.LennardJones(**kwargs)[source]

Basic calculator implementation.

restart: str

Prefix for restart file. May contain a directory. Default is None: don’t restart.

ignore_bad_restart_file: bool

Ignore broken or missing restart file. By default, it is an error if the restart file is missing or broken.

directory: str

Working directory in which to read and write files and perform calculations.

label: str

Name used for all files. Not supported by all calculators. May contain a directory, but please use the directory parameter for that instead.

atoms: Atoms object

Optional Atoms object to which the calculator will be attached. When restarting, atoms will get its positions and unit-cell updated from file.

Morse

class ase.calculators.morse.MorsePotential(**kwargs)[source]

Morse potential.

Default values chosen to be similar as Lennard-Jones.

Basic calculator implementation.

restart: str

Prefix for restart file. May contain a directory. Default is None: don’t restart.

ignore_bad_restart_file: bool

Ignore broken or missing restart file. By default, it is an error if the restart file is missing or broken.

directory: str

Working directory in which to read and write files and perform calculations.

label: str

Name used for all files. Not supported by all calculators. May contain a directory, but please use the directory parameter for that instead.

atoms: Atoms object

Optional Atoms object to which the calculator will be attached. When restarting, atoms will get its positions and unit-cell updated from file.