# position

Define a center-of-mass position for a group of atoms This command can appear in the global context.

### Options

atoms

Atoms in the group (1-indexed).

This option is mandatory.

• The type is [int]
• There is no default value.
• The value must be positive
final

Final reference position (in angstroms) for the center of mass. This keyword is used only for steered molecular dynamics. If not supplied, the initial_value will be used.

• The type is (real, real, real)
• There is no default value.
initial

Initial reference position (in angstroms) for the center of mass. This keyword is used only for steered molecular dynamics. If not supplied, the starting position will be used.

• The type is (real, real, real)
• There is no default value.
value

Reference position (in angstroms) for the center of mass. If not supplied, the starting position will be used.

• The type is (real, real, real)
• There is no default value.