Rf spectroscopy of alkaline earth atoms

Theoretical description of series perturbation and nonadiabatic effects in 

For simplicity we shall consider the Ba atom, although precisely the same procedure could be carried out for any alkaline earth atom. We shall assume that Ba consists of an inert spherical closed shell Ba2+ core which has two electrons.3 The basic notion of the treatment of Van Vleck and Whitelaw2 is readily understood by looking at the energy level diagram of Fig. 17.1. Each one electron 

1 Low lying energy levels of Ba+ (—), Rydberg series of Ba (—) converging to them, and the continua (III) above each of them (from ref. 3). 

Using H0, we can write the time independent Schroedinger equation as 

While the perturbation of the 6sni Rydberg series typically comes from the interaction with a single 5dn T state, core polarization comes from the interaction 

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