> interior {> ior 2.418> dispersion 1.044
Since the ior's range from about 2.407 to 2.452 (different charts have
different ranges), the ior should be set to (2.407+2.452)/2, or about
2.429, with a dispersion of (2.452/2.407), or about 1.0187. If you're not
as picky about the precision, try 2.43 and 1.019.
