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### compute erotate/asphere command

Syntax:

    compute ID group-ID erotate/asphere

- ID, group-ID are documented in compute command
- erotate/asphere = style name of this compute command

Examples:

    compute 1 all erotate/asphere

Description:

Define a computation that calculates the rotational kinetic energy of a group of aspherical particles. The aspherical particles can be ellipsoids, or line segments, or triangles. See the atom_style and read_data commands for descriptions of these options.

For all 3 types of particles, the rotational kinetic energy is computed as 1/2 I w^2, where I is the inertia tensor for the aspherical particle and w is its angular velocity, which is computed from its angular momentum if needed.

IMPORTANT NOTE: For 2d models, ellipsoidal particles are treated as ellipsoids, not ellipses, meaning their moments of inertia will be the same as in 3d.

Output info:

This compute calculates a global scalar (the KE). This value can be used by any command that uses a global scalar value from a compute as input. See Section_howto 15 for an overview of LAMMPS output options.

The scalar value calculated by this compute is "extensive". The scalar value will be in energy units.

Restrictions:

This compute requires that ellipsoidal particles atoms store a shape and quaternion orientation and angular momentum as defined by the atom_style ellipsoid command.

This compute requires that line segment particles atoms store a length and orientation and angular velocity as defined by the atom_style line command.

This compute requires that triangular particles atoms store a size and shape and quaternion orientation and angular momentum as defined by the atom_style tri command.

All particles in the group must be finite-size. They cannot be point particles.

Related commands: none

compute erotate/sphere

Default: none