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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 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.

IMPORTANT NOTE: For 2d models, 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 this section 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 particles be represented as extended ellipsoids and not point particles. This means they will have an angular momentum and a shape which is determined by the shape command.

This compute requires that atoms store angular momentum and a quaternion to represent their orientation, as defined by the atom_style. It also require they store a per-type shape. The particles cannot store a per-particle diameter or per-particle mass.

All particles in the group must be finite-size. They cannot be point particles, but they can be aspherical or spherical.

Related commands: none

compute erotate/sphere

Default: none