Spin-Orbit Autoionization

The method used in these calculations is based on the theoretical developments of Sakimoto [42] and is also an extension of our previous work on the Stark spectrum of spin-orbit autoionized Rydberg states of argon [43] and of the vibrationally autoionized states of hydrogen [44, 45], Only the homoge-... 

The magnitude of the spin-orbit splitting of the ion-core state affects the autoionization width most importantly through the minimum value of n, not through the size of I. This result is not surprising, since the present treatment was based on case (c) basis functions, which are eigenfunctions of the spin-orbit Hamiltonian (i.e., which diagonalize the spin-orbit part of the total Hamiltonian). (See Lefebvre-Brion, et al, (1985) for a theoretical treatment of the HI spin-orbit autoionization.)... 

Figure 8.15 Photoionization of HI at 0.14 A resolution showing the spin-orbit autoionization between the two fi = and = 4 thresholds of the ground state of the HI+ ion [from Eland (1980)].

In conclusion, Table 8.2 shows that the strongest autoionization process is electronic autoionization for light molecules and spin-orbit autoionization for... 

Softley (1993). Here we will analyze the effect of spin-orbit autoionization on ZEKE line intensities, for the example of HC1, where the ion-core ground state is a 2IIt state. 

This opposite branching behavior observed in the ZEKE spectrum can be explained if one considers the effect of spin-orbit autoionization. The contribution of spin-orbit autoionization to the decay by autoionization (hence loss of those molecules to the ZEKE signal) of the high-n Rydberg states, during the delay time, differently affects the intensity of the two spin-orbit components. 

Figure 8.21 ZEKE-PFI spectrum resulting from ionization via the P(3) rotational transitions associated with the F1 A2(u" = 0, J" = 2e) state of HC1. Upper panel observed (de Beer, et al., 1993) middle panel calculated for direct ionization lower panel calculated taking into account the population decay by spin-orbit and rotational autoionization after a delay of 200 ns (from Lefebvre-Brion, 1996)...

Those Rydberg states converging to the J+ =3/2 first rotational level of 2n3/2 cannot decay because all autoionization channels are closed. Those states converging to the other rotational levels of 2n3/2 can decay in the lower J+ levels of 2n3/2 only by what has improperly been called rotational autoionization (improper because it is due in part to spin-orbit interaction), with lifetimes for the d complex (n = 600) between 100 ns and 10-6 s. However, the high-n Rydberg levels converging to 2n1/2 rotational levels can decay into the rotational levels of both 2n3/2 and 2Hi/2 and their lifetimes are shorter than 10 6 s. 

The widths and profiles of Miv-v absorption lines jnovide important information on the 4f potential barrier which shields 4f electrons fiom the external electrons in a R solid. This effect is more or less visible in the widths and profiles of absorption lines. The lines in the Mv spin-orbit group are almost symmetric and are well represented by a Lorentzian shape. The Miv lines are asymmetric and exhibit a Fano-like profile. Final states with either 3ds/2 or 3ds/2 core holes decay primarily by Auger transitions. The fluorescence decay is small (Connerade and Kamatak 1981). States built on the 3d3/2 hole state have an additional decay channel, leading to autoionization if they interact with... 

Photoelectron spectroscopy Autoionization Koopmans approxlmaton Electron correlation Electron relaxation Closed shell systems Jahn-Teller effect Spin-orbit coupling Open shell systems Cross-sections, ligand Cross-sections, metal... 

The non-Franck-Condon intensities observed in the lower ( 113/2) spin-orbit state spectrum were attributed to autoionization involving another Rydberg series which converges to a higher... 

The vibrational progressions can be adequately simulated through the calculation of Franck-Condon factors however the observed spin-orbit branching ratio, along with the intensity distribution, reflects a considerable contribution from both spin-orbit and field-induced resonant autoionization processes. Also, accidental resonances at the two-photon level with ion-pair states further perturb the distribution of peak intensities. 

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