Structural and luminescent properties of Eu3+ doped Gd17.33(BO3)4(B2O5)2O16
Abstract
Crystal structure of gadolinium borate Gd17.33(BO3)4(B2O5)2O16 has been refined by the Rietveld method from X-ray powder diffraction data. Gd17.33(BO3)4(B2O5)2O16 crystallizes in the monoclinic space group Cm with lattice constants a=1841.70(3), b=374.08(1), c=1419.30(3) pm and β=119.85(1)°. The structure contains two types of borate groups BO33– and B2O54– , and nine independent gadolinium atoms. IR, Raman and HREM studies supported the presence of these two different borate groups in the structure. The luminescent spectra of the Eu3+ doped material consist of several sharp lines originating from the optical transitions within the f6 configuration of the Eu3+ ions at different cation sites.