SYNTHESIS AND CRYSTAL-STRUCTURE OF SR2ZNN2 AND BA2ZNN2

Ternary nitrides, Sr2ZnN2 and Ba2ZnN2, were prepared from Sr or Ba alo ng with Zn metal using Na metal and NaN3 as a flux and nitrogen source , respectively. The single crystals were obtained by slow cooling from 750 degrees C. Since these compounds hydrolyze in moist air, the crys tals were isolated by washing away excess Na with liquid NH3 in an ine rt environment. The structures were determined by single crystal X-ray diffraction: tetragonal, space group I 4/mmm with Z = 2, a = 3.8568(2 ), c = 12.935(1); Angstrom and R 1 = 0.049 for Sr2ZnN2, and a = 4.152( 1), 13.055(3) Angstrom, and R 1 = 0.039 for Ba2ZnN2. Sr2ZnN2 and Ba2Zn N2 are isostructural with Ca2ZnN2 (Na2HgO2 type) and contain linear [N =Zn=N](4-) nitridometallate anions. (C) 1995 Academic Press, Inc.