private List<List<Integer>> calcOrbits() {
		int n = subunits.getSubunitCount();

		List<List<Integer>> orbits = new ArrayList<List<Integer>>();
		for (int i = 0; i < n; i++) {
			orbits.add(Collections.singletonList(i));
		}

		return orbits;
	}
private List < List < Integer > > calcOrbits ( ) { int n = subunits . getSubunitCount ( ) ; List < List < Integer > > orbits = new ArrayList < List < Integer > > ( ) ; for ( int i = 0 ; i < n ; i ++ ) { orbits . add ( Collections . singletonList ( i ) ) ; } return orbits ; }
Returns a list of list of subunit ids that form an "orbit", i.e. they
are transformed into each other during a rotation around the principal symmetry axis (z-axis)
@return