private List[] splitParticlesByCharges() {
		List[] list = new List[2];
		list[0] = new ArrayList<Atom>();
		list[1] = new ArrayList<Atom>();
		for (int i = 0; i < numberOfAtoms; i++)
			list[atom[i].charge != 0 ? 0 : 1].add(atom[i]);
		return list;
	}