Plasma-assisted synthesis and properties of Na(3)N

Dark-blue sodium nitride, Na(3)N, was prepared by the reaction of metallic sodium or liquid Na-K alloy with plasma-activated nitrogen at low pressure. The compound crystallizes in the cubic anti-ReO(3)-type structure (space group Pm3m with a = 4.73301(6) Angstrom and Z = 1) according to powder and single-crystal X-ray diffraction data. Na(3)N decomposes above 104 degrees C into the elements, with DeltaH(f) estimated at +64(2) kJ/mol.