Rydberg states lifetimes

Such long lifetimes are puzzling in view of the well-known n3 scaling of Rydberg state lifetimes observed from linewidths of resolvable series and predicted by theory. The n3 scaling derives from a fundamental property of Rydberg states. The normalization factor in the radial part of the Rydberg orbital scales as n 3/2. Thus... 

If these shift data really do represent the onset of an intermolecular electron transfer reaction in DABCO, ABCO, HMT clustered with amine, either, and aromatic solvents, one ought to be able to observe the reaction kinetics or dynamics. Consider the specific instance of DABCO. The singlet Rydberg state lifetime for DABCO (and all the other Rydberg molecules studied for this determination (Shang et al. 1993c, 1994a) is ca. 2 ps for the isolated molecule and ca. 1.2 ps for the nonpolar rare gas, hydrocarbon, and fluorocarbon solvents. This... 

If we suppose that these Rydberg states have non-negligible lifetimes against autoionization, as could occur via dispersion of the potential energy of the molecule into various vibrational modes, then these states would be very sensitive to electric fields in the measuring apparatus. It is suggested here that this is the reason for the large discrepancies between cross sections measured in the various beam experiments. 

V. Engel Let me come back to the distribution of lifetimes of the ZEKE Rydberg states. I wonder if there is a simple picture behind. Consider a much simpler molecule, namely the Nal molecule Prof. Zewail told us about. There you have a bound state coupled to a continuum. It can be shown that in such a system the lifetimes of the quasibound states oscillate as a function of energy. In fact, Prof. Child showed with the help of semiclassical methods that there are lifetimes ranging from almost infinity to zero [1]. That can be understood by the two series (neglecting rotation) of vibrational levels obtained from the adiabatic and diabatic picture. If two energy levels of different series are degen-... 

M. Chergui Let me invoke a rather exotic behavior of Rydberg states that may or may not relate to the lifetime lengthenings discussed in the previous talk. 

Figure I. Lifetime of the n = 3 Rydberg states of NO in Ne, Ar, Kr, and Xe matrices atomic polarizability.

Figure 11 shows the calculated photoionization spectra in the region of n = 90 for various fields in the range 0.001-2 V/cm. A step size of 10-4 cm-1 was used in the calculations. At 0.001 V/cm (Fig. 1 la) the 92s (sharp) and 90d (broad) Rydberg states appear strongly, and from the linewidths we infer that the lifetimes are approximately 3.8 and 0.2ns, respectively. At 0.1 V/cm the n = 90 manifold appears superimposed on the tail of the 90d resonance. The manifold levels are sharper than the s and d resonances and... 

The lifetimes of alkali Rydberg states can be calculated accurately, as shown by Theodosiou,29 who has made extensive comparisons between observed lifetimes and calculated values. From this work is is also apparent that the black body radiation correction of Eq. (4.16) is important for high lying states. In light of these two points, it seems that the most compact and consistent way of presenting the alkali lifetimes is by a fit of the calculated 0 K values to the form31... 

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