Synthesis, Crystal Structure, Symmetry Relationships, and Electronic Structure of Bismuth Carbodiimide Bi(NCN) and Its Ammonia Adduct Bi(NCN)·NH.

Bi(NCN), the first binary pnictogen carbodiimide, and its ammonia derivative Bi(NCN)·NH have been prepared via nonaqueous liquid-state low-temperature ammonolysis. The crystal structure of Bi(NCN)·NH in space group solved via single-crystal X-ray diffraction corresponds to a two-dimensional-like motif with layers of NCN alternating with honeycomb-like layers of edge-sharing distorted BiN octahedra, half of which are also coordinated by molecular ammonia occupying the octahedral holes. By contrast, Bi(NCN) adopts a higher-symmetric 2/ structure with a single Bi position and stronger distortion but empty octahedral voids.

Can we trust the experiment? Anisotropic displacement parameters in 1-(halomethyl)-3-nitrobenzene (halogen = Cl or Br).

1-(Chloromethyl)-3-nitrobenzene, CHNClO, and 1-(bromomethyl)-3-nitrobenzene, CHNBrO, were chosen as test compounds for benchmarking anisotropic displacement parameters (ADPs) calculated from first principles in the harmonic approximation. Crystals of these compounds are isomorphous, and theory predicted similar ADPs for both. In-house diffraction experiments with Mo Kα radiation were in apparent contradiction to this theoretical result, with experimentally observed ADPs significantly larger for the bromo derivative.

Syntheses and Characterization of Diammine-Nickel/Cobalt(II)-Bisdicyanamide M(NH)[N(CN)] with M = Ni and Co.

Crystals of M(NH)[N(CN)] with M = Ni and Co were obtained from the reaction of stoichiometric amounts of Na[N(CN)] with NiCl·6HO or CoCl·6HO in aqueous, ammoniacal solutions. X-ray single-crystal structure analyses show that M(NH)[N(CN)] with M = Ni and Co crystallize isotypically to each other and adopt the monoclinic space group P2/ c (no. 14).