Permanent electric dipole moments of metal containing molecules

A summary of the current status of experimentally derived values of the per manent electric dipole moment, mu, for the 3s, 4s, 5s, and 6s series of tra nsient metal containing molecules is given. The experimental methods employ ed are described with particular emphasis placed upon optical Stark measure ments of supersonic molecular beam samples. The complications associated wi th the analysis of optical Stark spectra of open shell polyatomic metal con taining radicals are addressed. An assessment of the applicability of simpl e molecular orbital correlation diagrams to predict trends in measured Valu es of mu for early transition metal diatomic molecules is made.