Between Oxoborate and Nitridoborate: The Oxonitridoborate Oxide La3(OBN2)O2

The new compound La-3(OBN2)O-2 was prepared by a solid state reaction of LaOCl and Li-3(BN2) at 1200 degrees C in a fused niobium ampoule. A single crystal structure refinement [Pnma, Z = 4, a = 1269.8(2) pm, b = 368.94(5) pm, c = 1101.1(2) pm] indicates the pres-ence of a planar (OBN2)(5)-ion, which is structurally related to the (BN3)(6-) ion. The arrangement of atoms in the structure corresponds to a slightly modified structure of Ca-3(CBN)Cl-2 [Pnma, Z = 4, a = 1386.7(9) pm, b = 384.7(3) pm, c = 1124.7(6) pm].