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### dipole command

Syntax:

    dipole I value

- I = atom type (see asterisk form below)
- value = dipole moment (dipole units)

Examples:

    dipole 1 1.0
    dipole 3 2.0
    dipole 3*5 0.0

Description:

Set the dipole moment for all atoms of one or more atom types. This command is only used for atom styles that require dipole moments (atom_style dipole). A value of 0.0 should be used if the atom type has no dipole moment. Dipole values can also be set in the read_data data file. See the units command for a discussion of dipole units.

Currently, only atom_style dipole requires dipole moments be set.

I can be specified in one of two ways. An explicit numeric value can be used, as in the 1st example above. Or a wild-card asterisk can be used to set the dipole moment for multiple atom types. This takes the form "*" or "*n" or "n*" or "m*n". If N = the number of atom types, then an asterisk with no numeric values means all types from 1 to N. A leading asterisk means all types from 1 to n (inclusive). A trailing asterisk means all types from n to N (inclusive). A middle asterisk means all types from m to n (inclusive).

A line in a data file that specifies a dipole moment uses the same format as the arguments of the dipole command in an input script, except that no wild-card asterisk can be used. For example, under the "Dipoles" section of a data file, the line that corresponds to the 1st example above would be listed as

    1 1.0

Restrictions:

This command must come after the simulation box is defined by a read_data, read_restart, or create_box command.

All dipoles moments must be defined before a simulation is run (if the atom style requires dipoles be set). They must also all be defined before a set dipole or set dipole/random command is used.

Related commands: none

Default: none