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Breakdown of ionic character of molecular alkali bromides in inner-valence photoionization
A Karpenko1, D Iablonskyi1, S Urpelainen1
1Department of Physical Sciences, University of Oulu, Box 3000, FI-90014 Oulu, Finland.
Abstract:
The inner-valence region of alkali bromide XBr (X=Li, Na, K, Rb) vapours has been studied experimentally by means of synchrotron radiation excited photoelectron spectroscopy. Experimental spectra were analyzed by comparing them with available theoretical results and previous experiments. Ionic character of alkali bromides is seen to change in the inner-valence region with increasing atomic number of the alkali atom. A mechanism involving mixing between Br 4s and Rb 4p orbitals has been suggested to account for the fine structure observed in inner-valence ionization region of RbBr.
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