Rydberg electron oscillator strength

Both theoretical122-124 and experimental125 studies of the behavior of f0n versus q show that at qa0 < 1 the oscillator strengths for optically allowed transitions rapidly fall with increase of q, which is in agreement with formula (4.27). However, at qa0 > 1 the behavior of/0n( ) depends on the type of a transition. In the case of Rydberg transitions, f0n(q) has characteristic maxima and minima that are absent in the case of excitation of valence electrons. According to Ref. 123, their appearance is due to the existence of nodes in molecular orbitals. 

PeyerimhofT, S. D. and Buenker, R. J., Cl Calculations of vertical excitation energies and oscillator strengths for Rydberg and valence states of molecules, in Excited States in Chemistry C. A. Nikolaides and D. R. Beck (Eds.), Reidel, Dordrecht, 1978, p. 79. A survey of calculations of the electronic spectra of molecules using multireference doubleexcitation Cl (MRD-CI). MRD-CI includes single and double excitations relative not only to the Hartree-Fock wave function (Yq) but also relative to other important configurations (which may themselves be doubly excited with respect to Tq). Thus MRD-CI effectively includes higher than double (e.g., quadruple) excitations from Yg and hence can be essentially size consistent for moderate sized molecules. Other articles found in this book are also recommended. 

The electronic structure of Rydberg states can be probed by a large variety of atomic properties such as term values, lifetimes, oscillator strengths, Zeeman splitting factors. Stark and diamagnetic shifts, as well as... 

Figure 3.3 displays the calculated HOMO HOMO-3 and Rydberg 3py of n-hexane. Among these MOs, HOMO-l(Tt) and HOMO-2(a) are relevant to the electronic dipole-allowed transitions. Transitions from these MOs to Rydberg 3py and 3px have large oscillator strength as noted above, while those from HOMO (ag) have small intensities and those from HOMO-3 (au) are dipole forbidden. 

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