Inorganic Chemistry, Vol.50, No.19, 9545-9553, 2011
New Ternary and Quaternary Barium Nitride Halides; Synthesis and Crystal Chemistry
New ternary and quaternary nitride halides, Ba2N(X,X') (X = F, Cl, Br; X' = Br, I), have been synthesized from the high temperature reactions of barium subnitride with the respective barium halides under an inert atmosphere. The former include the first fully characterized barium nitride halides for X other than F, and the latter are the first examples of barium nitride mixed halides. The variation in structure with composition has been investigated by powder X-ray and powder neutron diffraction techniques. The heavier ternary and quaternary nitride halides (X, X' = Cl, Br, I) crystallize in the hexagonal space group R$(3)over bar $m, with the anti-alpha-NaFeO2 structure. Ba2NF forms with both an anti-alpha-NaFeO2 structure, in which N3- and F- are ordered and an anion-disordered simple rock salt structure. The hexagonal polymorph of Ba2NF is the only example to date of a nitride fluoride adopting this layered structure. Both the ternary and the quaternary compounds display very weak, temperature independent; paramagnetism.