void checkNeighborList() {
		double dispmax = 0.0;
		for (int i = 0; i < numberOfAtoms; i++) {
			dispmax = Math.max(dispmax, Math.abs(atom[i].rx - rx0[i]));
			dispmax = Math.max(dispmax, Math.abs(atom[i].ry - ry0[i]));
		}
		dispmax = 2.0 * Math.sqrt(3.0 * dispmax * dispmax);
		updateList = dispmax > rList - rCutOff;
	}