Strong dynamical effects in the K β2 and L γ2,3 X-ray emission spectra of lanthanum

Abstract

The K β 1,3 (K å M 3,2), K β 2 I, II (K å N 3,2), and the L γ 2,3 (L 1 å N 2,3) X-ray emission spectra from lanthanum have been measured, using high resolution crystal spectrometers. For the first time we observe an undisturbed 4 p 3 2 hole state together with a 4 p 1 2 hole state that is spread over an extended energy range. In comparison with theoretical calculations we show that in this case the quasi-particle picture only breaks down for the 4 p 1 2 core hole, due to very strong dynamical dipolar fluctuation and associated decay processes of the 4 p 1 2 core hole.