摘要
Europium (Eu￣(3+)) doped polycrystalline (LaO)_3BO_3 has been synthesized by solid state reaction with Li_2CO_3 as flux at 1200℃ for 10 h in air. X- ray powder diffraction shows that ( LaO)_3BO_3 crystallizes in a monoclinic cell [a= 0. 69214 (9)nm , b=1. 2929(3) nm , c=1. 4590 (3 ) nm . β= 99. 35 (2)°,V= 1. 2882(4 ) nm￣3 and Z= 8] with a possible space group of P2_1/m or P2_1. The predominance of electric-dipole transition ￣5D_0→ ￣7F_2 in the fluorescence spectrum , as well as the splitting of the￣7F_j ground states of Eu￣(3+) reveals that the lanthanum atoms distribute in the sites with C_1 or C_s symmetry in this structure.
Europium (Eu￣(3+)) doped polycrystalline (LaO)_3BO_3 has been synthesized by solid state reaction with Li_2CO_3 as flux at 1200℃ for 10 h in air. X- ray powder diffraction shows that ( LaO)_3BO_3 crystallizes in a monoclinic cell [a= 0. 69214 (9)nm , b=1. 2929(3) nm , c=1. 4590 (3 ) nm . β= 99. 35 (2)°,V= 1. 2882(4 ) nm￣3 and Z= 8] with a possible space group of P2_1/m or P2_1. The predominance of electric-dipole transition ￣5D_0→ ￣7F_2 in the fluorescence spectrum , as well as the splitting of the￣7F_j ground states of Eu￣(3+) reveals that the lanthanum atoms distribute in the sites with C_1 or C_s symmetry in this structure.
