Crystal structure of sodium rare earth oxyborates Na{sub 2}Ln{sub 2}(BO{sub 3}){sub 2}O (Ln = Sm, Eu, and Gd) and optical analysis of Na{sub 2}Gd{sub 2}(BO{sub 3}){sub 2}O:Eu{sup 3+}

Journal Article · Thu Apr 01 04:00:00 EST 1999 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1006/jssc.1998.8107· OSTI ID:349921

Corbel, G; Leblanc, M ^[1]; Antic-Fidancev, E; Lemaitre-Blaise, M ^[2]

---

1. Univ. du Maine, Le Mans (France). Lab. des Fluorures
2. ENSCP, Paris (France). Lab. de Chimie Appliquee de l`Etat Solide

A new structural family of rare earth oxyborates Na{sub 2}Ln{sub 2}(BO{sub 3}){sub 2}O (Ln = Sm, Eu and Gd) is evidenced. The structure, determined by single crystal X-ray diffraction, is monoclinic, space group P2{sub 1}/c, Z = 4, with a = 10.695(6) {angstrom}, b = 6.320(4) {angstrom}, c = 10.3228(6) {angstrom}, {beta} = 117.80(4){degree}, V = 617.5(9) {angstrom}{sup 3}, R{sub 1} = 0.039, wR{sub 2} = 0.101 for Na{sub 2}Gd{sub 2}(BO{sub 3}){sub 2}O. The three-dimensional network is built up from infinite sheets of LnO{sub 8} polyhedra in the (b,c) plane, which are separated by sodium ions. The luminescence of trivalent europium in polycrystalline Na{sub 2}Gd{sub 2}(BO{sub 3}){sub 2}O:Eu{sup 3+} is analyzed at 77K. The low symmetry of the rare earth sites, deduced from the X-ray diffraction study, is confirmed. The crystal field strength is high for both europium sites.

• OSTI ID: 349921
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 1 Vol. 144; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BORON OXIDES
CRYSTAL STRUCTURE
EUROPIUM
EUROPIUM OXIDES
EXCITATION
EXPERIMENTAL DATA
GADOLINIUM OXIDES
LASERS
LATTICE PARAMETERS
LUMINESCENCE
SAMARIUM OXIDES
SODIUM OXIDES
X-RAY DIFFRACTION