A BARIUM GERMANIUM NITRIDE, BA3GE2N2, CONTAINING (1)(INFINITY)VERTICAL-BAR-GE2- AND GEN24- ANIONS

Single crystals of a ternary nitride, Ba3Ge2N2, were synthesized by th e reaction of a and Ge with N from NaN3 in a Na melt by slow cooling f rom 750 degrees C. The structure, as determined by single crystal X-ra y diffraction, is monoclinic, space group PZ, int with Z = 2, and has lattice parameters a = 9.6196(6): b = 4.0466(2), c = 10.1337 Angstrom, beta = 113.553(4)degrees. The structure consists of angular nitridome tallate anions of [GeN2](4-) and prisms of [Ba3Ge](4+) condensed in on e dimension to form zigzag Zintl anions (1)(proportional to)\Ge2-. The Ge-N Bond length in the [GeN2](4-) aaions (1.88 Angstrom) is similar to those found in linear MN(2)(z-) anions, while the Ge-Ge bond in the Ge2- chains (2.50 Angstrom) is only slightly larger than in elemental Ge (2.45 Angstrom).