Evidence of Anionic Disorder in Fluoride Borate Eu3(BO3)2F3 from Eu3+ Luminescence: Comparison with Fluoride Carbonate Ba2Eu(CO3)2F3

✍ Scribed by Elisabeth Antic-Fidancev; Gwenaël Corbel; Nicolas Mercier; Marc Leblanc

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 202 KB
• Volume: 153
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.2000.8754

✦ Synopsis

The optical behavior of europium 6uoride borate Eu 3 (BO 3 ) 2 F 3 and barium 6uoride carbonates Ba 2 Eu(CO 3 ) 2 F 3 is investigated with Eu 3؉ as a local structural probe. Tentative correlation between the optical and structural data are discussed. Unexpected broad emission lines are observed for Eu 3؉ in 6uoride borate and the separation of two crystallographic sites, predicted from the structure determination, is impossible. It is assumed that deviation from the ideal stoichiometry Eu 3 (BO 3 ) 2 F 3 occurs and is due to the substitution BO 3؊ 3 3F ؊ , leading to the formulation Eu 3 (BO 3 ) 2؉x F 3؊3x . Crystal 5eld analysis is performed on the 7 F J basis of the 4f 6 con5guration of Eu 3؉ . The crystal 5eld parameters (cfp) and crystal 5eld strength parameter N V are similar for both compounds though slightly larger for Eu 3 (BO 3 ) 2 F 3 This di4erence is especially signi5cant for two rank (cfp), indicative of a larger electrostatic 5eld in Eu 3 (BO 3 ) 2 F 3 .