SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF SR2NBN3 AND BATHN2

Two ternary nitrides, Sr2NbN3 and BaThN2, have been synthesized by hea ting under flowing N-2 at 900 degrees C the appropriate molar mixtures of Sr2N and NbN, and Ba2N and Th3N4, respectively. The structure of S r2NbN3 was refined by the Rietveld method from X-ray powder diffractio n data. It crystallizes isotypically with Ba2TaN3 and Ba2ZnO3 [space g roup C2/c (No. 15); a = 5.9864(2) Angstrom; b = 11.2271(3) Angstrom; c = 12.5465(1) Angstrom; beta = 92.587(2)degrees, and Z = 8], Based on its powder X-ray diffraction pattern BaThN2 is believed to be isostruc tural with BaCeN2 and RbScO2 [space group P6(3)/mmc (No, 194); a = 3.7 523(6) Angstrom; c = 12.858(1) Angstrom, and Z = 2]. Magnetic suscepti bility data are consistent with the structural results. (C) 1998 Acade mic Press.