A straightforward, purely single-particle analysis of the Coulomb energy shift in Sc41, Ca41 leads to an abnormally small radius for the f72 valence neutron. Presented in this note is a correlational correction that may help to increase this radius. The calculation of this correction is stated in as general a fashion as is possible, and an estimate is made which leans heavily on a parametrization of the proton and neutron densities. © 1969 The American Physical Society.