Synthesis and Crystal Structure Analysis of Multinary Germanates and Stanates Containing Rare-earth Elements

在<10><12><0.8><2.4><0.8><1.5><0.5>稀土-Ca-Ge/Sn-O体系中，于1000 - 1500℃空气中固相反应合成了新化合物CaY_2Ge_3O_，CaY_2Ge_4O_，Ca_Y_Sn_O_6，Ca_Eu_3Sn_O_7。这些化合物的单晶通过退火或通过部分熔融的样品的缓慢冷却而获得。用单晶X射线衍射法分析了这些新化合物的晶体结构。CaY_2Ge_4O_2<12>与SrNa_2P_4O_3是同型的，<12>CaY_2Ge_3O_3<10>晶体结构新颖，Ca和Y原子无序地位于GeO_4四面体的独立萌发基团之间的3个7重配位上，<0.8>Ca_Y_Sn_O_6<2.4><0.8>与Mg_3TeO_6是同型的，而<1.5>Ca_Eu_3Sn_O_7<0.5>的晶体结构与B型Eu_2O_3的结构类似。<0.8>（Y_<1-x>Eu_x）_<2.4>Sn_<0.8>O_6（0.0 μ x&lt;0.3）Ca_<0.8>Y_<2.4>Sn_<0.8-y>Ti_yO_6（0.0 μ y ≤ 0.24）和Ca_<0.8>（Y_<0.9>）Eu_<0.1>）_<2.4>Sn_<0.8-y>Ti_yO_6（0.0 μ y ≤ 0.16）的发光性能进行了研究。在250-264 nm的紫外光照射下，Ca_<0.8>（Y_<0.9>）Eu_<0.1>）_<2.4>Sn_<0.72>Ti_<0.08>O_6和Ca_<0.8>（Y_<0.9>Eu_<0.1>）_<2.4>Sn_<0.8>O_6均显示出614 nm的明亮红光发射，这是由于<-7>Eu^&lt;3+的^5Do^ F_2跃迁所致。在Ca_ Y_ Sn_ Ti_ O_6中，Ti^&lt;4+&gt;的发射峰位于450 nm<0.8><2.4><0.72><0.08>处，表明Ti^&lt;4+&gt;向Eu^&lt;3+&gt;有能量转移的可能。

New compounds CaY_2Ge_3O_<10>, CaY_2Ge_4O_<12>, Ca_<0.8>Y_<2.4>Sn_<0.8>O_6, Ca_<1.5>Eu_3Sn_<0.5>O_7 were synthesized in the systems of rare-earth-Ca-Ge/Sn-O by solid state reaction at 1000 - 1500℃ in air. Single crystals of these compounds were obtained by annealing or by slow cooling of partially melted samples. The crystal structures of these new compounds were analyzed by the single crystal X-ray diffraction method. CaY_2Ge_4O_<12> is isotypic with SrNa_2P_4O_<12>, CaY_2Ge_3O_<10> crystallizes in a novel structure where Ca and Y atoms are situated disorderly in three 7-fold coordination sites between isolate germinate groups of triple GeO4 tetrahedra, Ca_<0.8>Y_<2.4>Sn_<0.8>O_6 is isotypic with Mg_3TeO_6, and Ca_<1.5>Eu_3Sn_<0.5>O_7 crystallizes in a novel structure which is related to the structure of B-form Eu_2O_3.Ca_<0.8>(Y_<1-x>Eu_x)_<2.4>Sn_<0.8>O_6 (0.0〓x<0.3) Ca_<0.8>Y_<2.4>Sn_<0.8-y>Ti_yO_6 (0.0〓y〓0.24) and Ca_<0.8>(Y_<0.9>)Eu_<0.1>)_<2.4>Sn_<0.8-y>Ti_yO_6(0.0〓y〓0.16) were prepared and investigated their luminescence properties. Under ultraviolet light irradiation of 250-264 nm, Ca_<0.8>(Y_<0.9>)Eu_<0.1>)_<2.4>Sn_<0.72>Ti_<0.08>O_6 and Ca_<0.8>(Y_<0.9>Eu_<0.1>)_<2.4>Sn_<0.8>O_6 showed bright red emission of 614 nm due to the ^5Do^<-7>F_2 transition of Eu^<3+>. A broad emission peak of Ti^<4+> centered at 450 nm was observed for Ca_<0.8>Y_<2.4>Sn_<0.72>Ti_<0.08>O_6, suggesting the possibility of energy transfer from Ti^<4+> to Eu^<3+>.