Rydberg defect

The important conclusion that can be drawn from the data is that 4/ electrons are distinctly external before barium and are located inside closed shells after cerium. The Rydberg defect d increases from 0.31 in Ba+ to 1.40 in La2+and the interelectronic repulsion parameter A (4f, 4 f) is 13 eV in La+ and 19.3 eV in Pr3+ in comparison to A (5s.5s) value of 6.3 eV for Y+. The interelectronic repulsion parameters A bear a close relationship with the reciprocal average radius of the orbital involved. We can define a generalized baricentre polynomial involving A for any element containing x electrons in the nl shell and y electrons in the n l shell as... 

Rydberg defect, eq. (1) standard oxidation potential electronic correlation energy... 

Ionic radii and coordination number N 114 D = spin-pairing energy parameter d — Rydberg defect... 

One of the conclusions from table 23.2 is that 4f electrons are distinctly external before barium and distinctly inside the closed shells after cerium, as first discussed theoretically by Maria Goeppert Mayer (1941). The Rydberg defect d increases from 0.31 in Ba to 1.40 in La" and A ,(4f, 4f) is already 13 eV in ha and 19.4 eV in Pr" to be compared with more usual values such as A, (5s, 5s) = 6.3 eV in Y. Although parameters such as A , are derived from... 

Here ERn is the energy of the Rydberg states, Er the ionization energy of the molecule, n the principal quantum number, S the quantum defect, and Ry the Rydberg constant. A measurement of the photoelectron spectrum immediately provides the Rydberg energies, because... 

The 3-photon ionization photoelectron spectrum, plotted as the photoelectron signal intensity as a function of the binding energy of the Rydberg states, is shown in Fig. 2. Three series of Rydberg peaks, with quantum defects of 0.93, 0.76, and 0.15 are obtained. From the quantum... 

H. J. Neusser In this regard, I should say that, up to now, the assignment of Rydberg triplet states has not been possible. In our high-resolution spectra only Rydberg series with a small quantum defect have been observed. It appears to be questionable whether triplet series become visible through spin-orbit coupling, which is expected to be small in a molecule like benzene. 

For small nonpolar species such as H2 and N2 the dominant interaction between the Rydberg electron and the nuclear vibrational and rotational motion occurs within a small radius around the ionic core, which is traversed in a fraction of a femtosecond. This short encounter justifies the sudden treatment of vibration and rotation in MQDT theory, while also permitting Bom-Oppenheimer estimates of the necessary quantum defect functions. It is also central to the n-3 scaling law because the core transit time is almost energy independent, while the Rydberg orbit time increases as n3. 

QUANTUM DEFECT THEORY OF THE DYNAMICS OF MOLECULAR RYDBERG STATES... 

A central feature of molecular quantum defect theory is the use of frame transformations. These provide an elegant way of treating the breakdown of the Bom-Oppenheimer approximation that occurs systematically once an electron is excited into a high Rydberg state. 

Ch. Jungen You are quite right. The Renner-Teller effect in the water ion is an example of this kind. The strong vibronic coupling in the core leads to nonadiabatic effects in the Rydberg states of the neutral species, which are of course not accounted for by the coordinate dependence of the quantum defect and have to be taken into account separately. 

With regard to your second remark I would like to say this The calculations I showed for CaF and BaF Rydberg states are examples where the core field is a Coulomb field but where a very strong dipole field is superimposed. Here we have used the generalized version of quantum defect theory, which takes account of this modified long-range field. 

There are two parameters in the atomic coulomb functions, the effective nuclear charge and the quantum defect. The values of these were taken by Johnson and Rice from available spectral data. The effective atomic charge was adjusted to give the correct ionization potential of the molecule, 9.25 eV, requiring thereby z = 0.8243. The quantum defects of carbon were taken from the appropriate atomic series and were 1.04 for the 5-state and 0.73 for the p-states. It is interesting to compare the calculated molecular quantum defects (i.e., those corresponding to the Johnson-Rice LCAO function) with those which can be obtained from the various benzene Rydberg series.218 The asymptotic form of the elu orbital constructed from s atomic functions is... 

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