Rydberg lanthanide

Blasse G (1976) The Influence of Charge-Transfer and Rydberg States on the Luminescence Properties of Lanthanides and Actinides. 26 43-79 Blasse G (1980) The Luminescence of Closed-Shell Transition Metal-Complexes. New Developments. 42 1-41... 

The Influence of Charge-Transfer and Rydberg States on the Luminescence Properties of Lanthanides and Actinides... 

The influence of charge-transfer and rydberg states on the luminescence of lanthanides... 

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. 

Ionization potentials of atoms are usually obtained by the determination of a photoionization threshold or more accurately by the observation of long Rydberg progressions. With the exception of a few of these elements with simple spectra, obtaining such measurements for lanthanides and actinides is difficult if not impossible by conventional spectroscopy. Therefore, very accurate ionization limits were not available for the majority of these elements.( 6)... 

The Rydberg series and photoionization thresholds obtained have permitted the accurate determination of ionization limits for uranium, (1) neptunium, and ten lanthanides. Q)... 

Some lanthanide Rydberg convergence limits derived from observed series by this method are given in Table II. The excitation wavelengths and levels from which the series were observed and the ion levels that they converge to are indicated in the table. Information on ionic states was obtained from the literature for Dy, t and where... 

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