Photoacoustic spectroscopy of Ln3+ (Nd, Ho, and Er) doped ThO2

Undoped and ThO2:Ln(3+) (Ln = Nd, Ho, and Er) were synthesized by wet chemical route and characterized using X-ray diffraction (XRD). PAS was used to investigate electronic absorption of Nd3+, Ho3+ and Er3+ in thorium dioxide as well as of pure rare earth oxide powder Ln(2)O(3) (Ln = Nd, Ho, and Er). PA spectra were also obtained for aqueous solution of lanthanides for evaluating various covalency parameters. Various covalency parameters like nephelauxetic ratio (beta), covalency factor (b(1/2)) and Sinha parameter (delta) were evaluated for pure oxide powder and for rare earth doped thoria for all these system from their individual PA spectra. (C) 2013 Elsevier B.V. All rights reserved.