Cover Feature: [A([18]crown‐6)]2[Ni(CO)3]·8NH3 (A = K, Rb) – An Ammoniate with a Trigonal Planar [Ni(CO)3]2– Anion (Z. Anorg. Allg. Chem. 24/2018)

The cover picture shows the molecular structure of the mononuclear tricarbonyl nickelate [Ni(CO)3]2– synthesized by dissolving a Zintl phase, a nickel complex and chelating agents in liquid ammonia. The planar anion evinces almost perfect D3h symmetry. The calculated isosurface of the electron localization function (ELF) shows plane basins above and below the molecular plane, where the electrons of the twofold negative charge are evenly distributed. More details are discussed in the paper by Korber et al. on page 1678 ff.