bone_branch [Id an atom]
An atom will be added to the object of the identified atom, connected to this atom but displaced (0.5, 0.5, 0.5)Å. It will be given the status code 2 (which usually specifies a side chain) and will initially appear as a white bond (this will change to the users specified colour when the next object is created). This command is useful to indicate the desired position for a CA atom when a branch point is lacking. It can also be used to extend a skeleton from a loose end (via repeated Bone_branch and Move_atom commands).