Single crystal structure and Raman spectrum of Ba3Na2(CN2)4

The synthesis, single crystal structure determination, and Raman spectrum are reported for colorless transparent tribarium disodium tetracyanamide, Ba₃Na₂(CN₂)₄. The title compound crystallizes in the space group C_2h⁵-P2₁/c (#14, , , , β=110.454(4)°, , Z=4, R/wR=0.0266/0.0543). Each sodium atom is surrounded by six nitrogen atoms in octahedral geometry. Sodium centered nitrogen octahedra are linked through face-sharing along the 100] direction to form one-dimensional (1D) chains. These chains are connected to each other through the carbon atoms of cyanamide and make a three-dimensional (3D) network with 1D channels along the 100] direction. Barium atoms and additional cyanamide anions reside in the channels. Each barium atom is irregularly coordinated with nitrogen and carbon from the cyanamide anions. The Raman spectrum shows symmetric vibrations of NCN]²⁻ corresponding to ν_sym (1241.5 cm⁻¹) and 2δ (1356.4 cm⁻¹).