Budget Amount *help |
¥3,200,000 (Direct Cost: ¥3,200,000)
Fiscal Year 1998: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1997: ¥2,400,000 (Direct Cost: ¥2,400,000)
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Research Abstract |
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.
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