EuCN₂ — The First, but Not Quite Unexpected Ternary Rare Earth Metal Cyanamide

Red‐orange, transparent single crystals of EuCN 2 ( Pnma (62), a = 1232.41(9), b = 395.26(3) and c = 539.43(4) pm, Z = 4) are obtained by the reaction of EuN, C and NaN 3 in arc‐welded Ta ampoules at 1300 K. The first ternary rare earth metal cyanamide is isotypic to α‐SrCN 2 and shows the characteristic frequencies for the CN 2 2— unit in the optical spectra (ν s = 1244; ν as = 1969 and 2087; δ = 655 / 666 cm —1 ).