Rydberg transitions

Fig. 2. The H-atom Rydberg transition spectrum from the n = 2 level to the higher n states.

Sandorfy, C. Electric Absorption Spectra of Organic Molecules Valence-Shell and Rydberg Transitions. 86,91-138 (1979). 

Electronic spectra of oxadiazoles were studied <2003IJB429>. MRINDO/S calculations augmented by singly excited Cl were performed on oxadiazoles. Net charge distributions, ionization potentials, and electronic spectra of oxadiazoles were reported. The Rydberg transitions were also discussed. 

As a general rule the c.t. bands shift to lower energies with increasing oxidation state, whereas Rydberg transitions (such as 4f- -5d transitions) shift to higher energies. It may, therefore, be expected that the lowest absorption bands of the tetravalent lanthanide ions will be due c. t. transitions and those of the divalent lanthanide ions to Af- -5d transitions. 

An electronic transition in which an electron is promoted from a bonding a orbital to an antibonding a orbital. The transition energies are often close to those of Rydberg transitions. See Absorption Spectroscopy Comm, on Photochem. (1988) Pure and Appl. Chem. 60, 1055. 

Bicyclo[1.1.0]butane has been studied in some detail. " Again, all of the states appear to involve Rydberg transitions. The transition energies are at lower energies than those for cyclopropane, which may be a result of the strain in the bicyclobutane ring that further increases the ground-state energy. The spectrum of [l.l.ljpropellane has not as yet been subjected to a detailed analysis. 

The ultraviolet spectra of saturated hydrocarbons are usually not very informative, and are dominated by Rydberg transitions.101 They correspond to the formation of a radical cation with the ejected electron being captured in a diffuse, atomlike orbital. Bicyclo[l.1. OJbutane is the most extensively studied molecule of this group, and the Rydberg nature of the excited... 

The spectrum of cyclopropane is rather similar in that it has only Rydberg transitions. The spectrum of cyclobutane is also dominated by Rydberg transitions, and its spectrum resembles that of the larger cycloalkanes, and is quite different to that for cyclopropane.104 Cyclopropene and cyclobutene have also been examined, and here a n -> n transition is seen along with the Rydberg transitions.101... 

As a conclusion, our experimental/simulation study of the supercritical Ar solvent response, upon a Rydberg transition, reveals a highly non-linear character of the medium reorganisation. Simple model systems, such as the one used here, may provide a working basis for the development of a formal description of the non-linear response in condensed phase media. 

Bromoacctylene is linear in the ground state D0(Br —C2H) = 3.95 0.05 eV (773). Its absorption starts at 2800 A. Above 1730 A there are two continuous absorption bands with maxima at 2115 and 1780 A, while below 1730 A a number of Rydberg transitions are observed with complicated vibrational structure [Thomson and Warsop (970), Evans et al. (338)]. 

Below 1800 A several Rydberg transitions have been found leading to an ionization potential of 11.329 0.002 eV [Bell et al. (93)]. The absorption coefficients in the region 2000 to 25(H) A have been measured by McMillan [quoted in (4), p. 428]. 

A second continuum lies in the region 1800 to 1950 A followed by various Rydberg transitions in the region 1070 to 1870 A [Lee and Walsh (621)]. 

Figure 38. (a) Emission spectrum (190-340 nm) from excited species formed in collisions of 10-eV H+ ions with NO (spectrum was taken with I-nm resolution major features are NO A—>X y bands, which are identified in diagram b) inset shows partial spectrum produced by impact of 30-eV H+ ions with NO (6-nm resolution) and indicates Rydberg-Rydberg transitions (b) model spectrum (vertical transitions) for the NO y bands.288... 

While ionization by linearly polarized fields has been well studied, there is only one report of ionization by a circularly polarized field, the ionization of Na by an 8.5 GHz field.36 In the experiment Na atoms in an atomic beam pass through a Fabry-Perot microwave cavity, where they are excited to a Rydberg state using two pulsed tunable dye lasers tuned to the 3s — 3p and 3p —> Rydberg transitions at 5890 A and —4140 A respectively. The atoms are excited to the Rydberg states in the presence of the circularly polarized microwave field which is turned off 1 fis after the laser pulses. Immediately afterwards a pulsed field is applied to the atoms to drive any ions produced by microwave ionization to a microchannel plate detector. To measure the ionization threshold field the ion current is measured as the microwave power is varied. 

Transitions in which the transition moment is at right angles to the internuclear axis are Q — N and the bands typically have low intensities. In molecular orbital terminology these are t - n transitions (9). Both V - N and Q - N transitions occur without a change in the principal quantum number and are valence shell transitions in contrast to Rydberg transitions, R - N where a change of the principal quantum number does occur. The symbol I describes a triplet state formed in a valence shell transition. 

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