Quantitative determination of F:O ratios in rare earth oxide fluorides by energy dispersive X-ray analysis.
The F:O ratio in homogeneous and inhomogeneous rare earth oxide fluoride systems of compositions RO(1+x)F(1-2x) with -0.1</=x</=0.1 can be determined by energy dispersive X-ray (EDX) analysis with an accuracy of +/-0.5% if an appropriate background modelling procedure is applied and if the EDX signals of the light elements are free of overlap from the accompanying rare earth element. The latter condition holds true for R=Tb-Lu and it is shown that the calibration of the method with well-defined samples of YbO(1+x)F(1-2x) can be transferred with only a moderate loss of accuracy to the determination of oxygen and fluorine in DyOF and ErOF. Increasing signal overlap in case of GdOF, EuOF, SmOF and especially PrOF necessitates the choice of different channels for background modelling, and the accuracy of the method is hence decreasing to +/-4% for these systems.
Marx
V
V
Department of Chemistry, Addis Abeba University, POB 1157, Addis Abeba, Ethiopia.
Greis
O
O
Strübig
H
H
Petzel
T
T
Müller
J H
JH