parmed.topologyobjects.PiTorsion

class parmed.topologyobjects.PiTorsion(atom1, atom2, atom3, atom4, atom5, atom6, type=None)

Defines a pi-torsion term in the AMOEBA force field. The Pi-torsion is defined around a sp2-hybridized pi-delocalized orbital (like an amide) by 6 atoms, as shown in the schematic below.

A2 A5-AAA

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A3—A4

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AAA-A1 A6

In the above schematic, A3 and A4 are sp2-hybridized, and atoms A2 and A6 are bonded only to A3 and A4, respectively. Atoms A1 and A5 are each bonded to 3 other atoms.

Parameters

atom1Atom

atom A1 in the schematic above

atom2Atom

atom A2 in the schematic above

atom3Atom

atom A3 in the schematic above

atom4Atom

atom A4 in the schematic above

atom5Atom

atom A5 in the schematic above

atom6Atom

atom A6 in the schematic above

typeDihedralType

The parameters for this Pi-torsion

Notes

Both :class:`Bond`s and :class:`Atom`s can be contained in a pi-torsion

__init__(atom1, atom2, atom3, atom4, atom5, atom6, type=None)

Initialize self. See help(type(self)) for accurate signature.

Methods

__init__(atom1, atom2, atom3, atom4, atom5, …)

Initialize self.