title: A series of novel rare-earth bismuth tungstate compounds LnBiW2O9 (Ln=Ce, Sm, Eu, Er): synthesis, crystal structure, optical and electronic properties.
abstract: The structural, optical, and electronic properties of four rare-earth bismuth tungstate compounds, LnBiW(2)O(9) (Ln = Ce, Sm, Eu, Er), have been investigated by means of single-crystal X-ray diffraction, elemental analyses, and spectral measurements. For some of the compounds, the calculations of energy band structures and density of states have also been made by the density functional theory. The structure of CeBiW(2)O(9) features a three-dimensional (BiW(2)O(9))(3-) anionic framework with interesting channels where Ce atoms are located. The framework is constructed by one-dimensional BiO(9) polyhedra chains and one-dimensional zigzag W(2)O(9) chains via edge- and face-sharing. LnBiW(2)O(9) (Ln = Sm, Eu, Er) are isostructural and their structures feature a three-dimensional network based on alternating (BiO(2))(-) layers and (Ln(2)W(2)O(12))(6-) layers connected by corner-linked chains of WO(6) octahedra. Results of spectral measurements indicate that EuBiW(2)O(9) exhibit the characteristic yellow-red light emission under excitation at 395 nm, and it will be a red phosphor in designing white light-emitting diode device. The calculated results of band structures by using the density functional theory (DFT) show that the solid-state compound CeBiW(2)O(9) and SmBiW(2)O(9) are indirect band gap materials.
authors.affiliation: State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, 350002, People's Republic of China.
authors.forename: Ye-Yu
authors.initials: YY
authors.lastname: Li
authors.forename: Wen-Dan
authors.initials: WD
authors.lastname: Cheng
authors.forename: Hao
authors.initials: H
authors.lastname: Zhang
authors.forename: Chen-Sheng
authors.initials: CS
authors.lastname: Lin
authors.forename: Wei-Long
authors.initials: WL
authors.lastname: Zhang
authors.forename: Lei
authors.initials: L
authors.lastname: Geng
authors.forename: Guo-Liang
authors.initials: GL
authors.lastname: Chai
authors.forename: Zhong-Zhen
authors.initials: ZZ
authors.lastname: Luo
authors.forename: Zhang-Zhen
authors.initials: ZZ
authors.lastname: He