code: public static double getMaximumExtend( final Structure structure ) {
  		double[][] bounds = getAtomCoordinateBounds(structure);
  		double xMax = Math.abs(bounds[0][0] - bounds[1][0]);
  		double yMax = Math.abs(bounds[0][1] - bounds[1][1]);
  		double zMax = Math.abs(bounds[0][2] - bounds[1][2]);
  		return Math.max(xMax, Math.max(yMax, zMax));
  	}
docs: Returns the maximum extend of the structure in the x, y, or z direction.
  @param structure
  @return maximum extend