The Family of Ln2Ti2S2O5 Compounds (Ln=Nd, Sm, Gd, Tb, Dy, Ho, Er, and Y): Optical Properties

✍ Scribed by C. Boyer-Candalen; J. Derouet; P. Porcher; Y. Moëlo; A. Meerschaut

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 403 KB
• Volume: 165
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.2002.9492

✦ Synopsis

The optical properties of Ln 2 Ti 2 S 2 O 5 compounds (Ln=Nd, Sm, Gd, Tb, Dy, Ho, Er, and Y) have been measured. Diffuse reflectance spectra revealed a strong absorption band above 2 eV, which explains the color of the compounds. Moreover, other bands, with a lower intensity, have been attributed to 4f-4f rare earth transitions. In the case of neodymium the derived energy level scheme is rich enough to determinate a set of phenomenological crystal field parameters that correctly reproduce the spectrum. These parameters were also calculated from the crystallographic structure, in a good agreement with the experiment. Finally, the paramagnetic susceptibility, well reproduced by the calculation, confirms that the rare earth is in a trivalent state.