Yb valence in Yb1-xCaxAl2 pseudobinary alloys via Yb LIII X-ray absorption spectroscopy

Abstract We present Yb L III near edge X-ray absorption spectra (XAS) for a series of Yb 1- x Ca x Al 2 (x = 0; 0.4; 0.6; 0.8) isostructural pseudobinary alloys. The Yb mean valence derived by intensity analysis of the Yb 2+ and Yb 3+ white lines of the XAS spectra results to gradually decrease as the Ca-content is progressively increased and, in turn, the nearest neighbours atomic shell surrounding the Yb sites is increasingly expanded.