Preparation of Multicomponent Nitrides and their Crystal Chemstry

以叠氮化钠（NaN3）为氮源，金属钠（Na）为助熔剂，尝试制备多组分氮化物。金属源用NaN3和Na密封在一个不锈钢管容器中，容器内壁覆盖着铌片。将该管置于氩气电炉中，750℃加热。加热后，将管冷却至室温。用液氨洗涤钠通量。为此设计了h型电池。用该方法制备了氮化镓锶单晶Sr_3Ga_2N_4。晶体尺寸小于1mm，呈薄片状，黄色，透明。x射线单晶结构分析表明，该化合物具有正交对称性(晶格参数：α = 5.9579(12), b = 10.285（2), c = 9.557(2) A，空间群P nna）。Sr_3Ga_2N_4与Sr_3Al_2N_4和Ba_3Ga_2N_4是同构的。Ga原子与4个氮原子配位形成四面体。四面体共用两条边，构成一维链。锶原子被六个氮原子包围。在Ba-Ti-N体系中也得到了红色透明单晶，而在Sr-Ti n体系中则没有。在含稀土元素的体系中得到了二元氮化物的混合物，且不能合成多组分氮化物。

Preparation of multi-component nitrides was attempted by using sodium azide (NaN3) as anitrogen source and sodium metal (Na) as a flux. Metal sources were sealed with NaN3 and Na in a stainless-steel tube container in which the inner wall was covered with a niobium sheet. This tube was placed in an electric furnace with argon gas and heated at 750ﾟC.After the heating, the tube was cooled to room temperature. The Na flux was washed with liquid ammonia. An H-shape cell was designed for this process. By using the present method, single crystals of strontium gallium nitride, Sr_3Ga_2N_4 were prepared. The crystals were below 1 mm in size, thin platelet, yellow, and transparent. X-ray single crystal structure analysis revealed that this compound has an orthorhombic symmetry (lattice parameters : alpha= 5.9579(12) , b = 10.285(2) , c = 9.557(2) A, space group P nna). Sr_3Ga_2N_4 is isostructural with Sr_3Al_2N_4 and Ba_3Ga_2N_4. Ga atoms were coordinated by four nitrogen atoms and form tetrahedra. The tetrahedra share two edges and make a one-dimensional chain. Strontium atoms are surrounded by six nitrogen atoms. Red color transparent single crystals were also obtained in the system of Ba-Ti-N, but not in the Sr-Ti N.Mixture of binary nitrides were obtained and multi-component nitrides could not be synthesized in the systems including rare-earth elements.