BaCISCN and Na4Mg(SCN)(6): Two new thiocyanates of the alkaline earth metals

The reaction of BaCl2 and NaSCN yielded single crystals of BaClSCN (P2(1)/m , Z = 2, a = 588.6(1)pm, b = 465.8(1) pm, c = 864.4(2) pm, beta =100.20(3)d egrees, R-all = 0.0214). According to X-ray single crystal investigations, the structure consists of anionic SCN- and Cl- layers, respectively, altern ating in [001] direction. The SCN--ions are connected via the N and the S a toms to the cations. Na4Mg(SCN)(6) (P (3) over bar 1c, Z = 2, a = 863.8(1) pm, c = 1399.3(2) pm, R-all = 0.0870), which was obtained from a melt of Na SCN and MgCl2, consists of anionic layers with the cations between the shee ts. The holes are filled altenatingly by Na+ or Na+ and Mg2+. Regarding onl y the C-atoms of the SCN- group, the structure can be described as a hexago nal closest packing whith the cations occupying 5/6 of the octahedral voids .