`TopologyKey`

pydantic model openff.interchange.models.TopologyKey[source]

Bases: DefaultModel, ABC

A unique identifier of a segment of a chemical topology.

These refer to a single portion of a chemical graph, i.e. a single valence term, (a bond, angle, or dihedral) or a single atom. These target only the information in the chemical graph and do not store physics parameters. For example, a TopologyKey corresponding to a bond would store the indices of the two atoms that compose the bond, but not the force constant or equilibrium bond length as determined by the force field.

Examples

Create a TopologyKey identifying some speicfic angle

>>> from openff.interchange.models import TopologyKey
>>> this_angle = TopologyKey(atom_indices=(2, 1, 3))
>>> this_angle
TopologyKey with atom indices (2, 1, 3)

Create a TopologyKey indentifying just one atom

>>> this_atom = TopologyKey(atom_indices=(4,))
>>> this_atom
TopologyKey with atom indices (4,)

Fields

atom_indices (tuple[int, ...])

field atom_indices: tuple[int, ...] [Required]: The indices of the atoms occupied by this interaction