Only the a6D-z6D multiplet has been measured by CBFG.
50V is blueshifted from 51V.

624.2829     -651.4 MHz    50-51 = -8 mA
627.4649     -650.8
623.0798     -652.1
628.5150     -651.7
621.6354     -650.7
625.1827     -649.7
619.9197     -648.8
624.3105     -647.6

CBFG      Cochrane, E.C.A., Benton, D.M., Foreset, D.H., and Griffith, J.A.R. 1998,
             J.Phys.B 31, 2203-2213,