Zr 2 N 2 Se: The First Zirconium(IV) Nitride Selenide by the Oxidation of Zirconium(III) Nitride with Selenium

The oxidation of zirconium(III) nitride (ZrN) with suitable amounts of selenium (Se) in the presence of sodium chloride (NaCl) as flux yields small yellow brownish platelets of the first zirconium(IV) nitride selenide with the composition Zr 2 N 2 Se. The new compound crystallizes in the hexagonal space group P 6 3 / mmc (no. 194) with a = 363.98(2) pm, c = 1316.41(9) pm ( c / a = 3.617) and two formula units per unit cell. The crystallographically unique Zr 4+ cations are surrounded by three selenide and four nitride anions in the shape of a capped trigonal antiprism. The Se 2– anions are coordinated by six Zr 4+ cations as trigonal prism and the N 3– anions reside in tetrahedral surrounding of Zr 4+ cations. These [NZr 4 ] 13+ tetrahedra become interconnected via three edges each to form $\rm^{2}_{\infty}$ {[(NZr 4/4 ) 2 ] 2+ } double layers parallel to the (001) plane, which are held together by monolayers of Se 2– anions.