Boron-Carbon Order and Symmetry Control: Single-Crystal X-Ray Study of SmB2C2

Abstract

The title compound was prepared from the elements by arc-melting followed by annealing in silica tubes at 1270 K for one week. The crystal structure was investigated by means of X-ray single crystal diffraction: space group P4/mbm, a = 5.366(1), c = 3.690(1) Å , Z = 2, R1 = 0.010, wR2 = 0.022 for 245 unique reflections with Io > 2σ (Io) and 12 refined parameters. Group-subgroup relationships of MB6 and MB2C2 structure models are discussed