摘要
La_(1.5)Sr_(7.0)Na_(1.5)(PO_4)_6X′X″(X′and X″stand for two identical or different halide ions F^-,Cl^-,and Br^-)is a new kind matrix of phosphors.X-ray analysis shows that these crystals belong to the apatite structure of hexagonal system with a space group of p6_(3/m).Their lattice parameters have been obtained.Subsolidus phase relationship in the double halophosphate systems were determined by lattice parameter method.It has been proved that in the Br-Cl and F-Cl systems there exist complete and continuous solid solutions.In the F-Br sys- tem there appears a two phase region with the bromide composition 0.75<Br<1.25. The variation of emission intensity of Ce^(3+)with the change of halogen composition has been observed. Fluorescence spectroscopic study unraveled that there exist two types of luminescent center in Ce^(3+)activated La_(1.5)Sr_(7.0)Na_(1.5)(PO_4)_6X′X″crystals.The temperature dependence of the peak wavelength was determined.As temperature is raised,emission bands shift towards blue.
La_(1.5)Sr_(7.0)Na_(1.5)(PO_4)_6X′X″(X′and X″stand for two identical or different halide ions F^-,Cl^-,and Br^-)is a new kind matrix of phosphors.X-ray analysis shows that these crystals belong to the apatite structure of hexagonal system with a space group of p6_(3/m).Their lattice parameters have been obtained.Subsolidus phase relationship in the double halophosphate systems were determined by lattice parameter method.It has been proved that in the Br-Cl and F-Cl systems there exist complete and continuous solid solutions.In the F-Br sys- tem there appears a two phase region with the bromide composition 0.75<Br<1.25. The variation of emission intensity of Ce^(3+)with the change of halogen composition has been observed. Fluorescence spectroscopic study unraveled that there exist two types of luminescent center in Ce^(3+)activated La_(1.5)Sr_(7.0)Na_(1.5)(PO_4)_6X′X″crystals.The temperature dependence of the peak wavelength was determined.As temperature is raised,emission bands shift towards blue.
基金
National Natural Science of China
