title: Crystal structures and luminescence properties of Eu²⁺-activated new NaBa0.5Ca0.5PO₄ and Na₃Ba₂Ca(PO₄)₃.
abstract: NaBa(1-x)Ca(x)PO4:Eu(2+) were synthesized using polymerizable complex method. New phases were observed at x = 1/3 and 0.5, which were identified by single-crystal XRD analysis as Na3Ba2Ca(PO4)3 and NaBa0.5Ca0.5PO4 with a trigonal system. Though both phases pretend to be solid solutions between NaBaPO4 and NaCaPO4, they have different coordination environments and PO4 orderings. 1 mol% Eu(2+)-activated NaBaPO4, Na3Ba2Ca(PO4)3, and NaBa0.5Ca0.5PO4 exhibited an emission maximum at 435 nm, 458 nm, and 460 nm, respectively. The shift of the emission maximum might be due to a change in the Eu-O bond length.
authors.affiliation: Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan. kakihana@tagen.tohoku.ac.jp.
authors.forename: Minsung
authors.initials: M
authors.lastname: Kim
authors.forename: Makoto
authors.initials: M
authors.lastname: Kobayashi
authors.forename: Hideki
authors.initials: H
authors.lastname: Kato
authors.forename: Hisanori
authors.initials: H
authors.lastname: Yamane
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Sato
authors.forename: Masato
authors.initials: M
authors.lastname: Kakihana