Synthesis and characterization of three new rare-earth orthoborates: Ba2MgY2(BO3)(4), Ba2CdY2(BO3)(4), and Ba2CdSc(BO3)(3)

摘要

Three rare-earth orthoborates Ba2MgY2(BO3)(4), Ba2CdY2(BO3)(4), and Ba2CdSc(BO3)(3) were synthesized via a high-temperature solution method and their structures were determined by single crystal X-ray diffraction for the first time. Ba2MgY2(BO3)(4) and Ba2CdY2(BO3)(4) are isostructural and both crystallize in the monoclinic crystal system, P2(1)/c, while Ba2CdSc(BO3)(3) crystallizes in the triclinic crystal system,P (1) over tilde;. The structures of Ba2MgY2(BO3)(4)and Ba2CdY2(BO3)(4) can be described as the three-dimensional (3D) frameworks composed of MO5(M = Mg, Cd), YOn (n= 6, 7) polyhedra with isolated BO(3)and Ba2+ cations residing in the space of the frameworks. The structure of Ba2CdSc(BO3)(3) is composed of 2D [CdSc(BO3)(3)](infinity) layers separated by Ba(2+)cations. In addition, structural comparisons, thermal behaviors, UV-vis-NIR diffuse reflectance spectra, and infrared spectroscopy results are also reported.