Detection of nanocrystallinity by X-ray absorption spectroscopy in thin film transition metal/rare-earth atom, elemental and complex oxides

Nanocrystallinity has been detected in the X-ray absorption spectra of transition metal and rare-earth oxides by (i) removal of d-state degeneracies in the (a) Ti and Sc L3 spectra of TiO2 and LaScO3, respectively, and (b) O K1 spectra of Zr(Hf)O2, Y2O3, LaScO3 and LaAlO3, and by the (ii) detection of the O-atom vacancy in the O K1 edge ZrO2-Y2O3 alloys. Spectroscopic detection is more sensitive than X-ray diffraction with a limit of ∼2 nm as compared to >5 mm. Other example includes detection of ZrO2 nanocrystallinity in phase-separated Zr(Hf) silicate alloys.