Mn2NiReO6, prepared at high pressure and temperature, has a highly-distorted double perovskite structure. Canted antiferromagnetic order is observed below TM1 = 80 K and an unusual continuous spin rotation of...

Reaction of Bi with Pb, Pt and BiI3 above 330 °C yielded shiny, black, air insensitive crystals of the subiodide Pb[PtBi6I12]. Pb[PtBi6I12] crystallizes in the rhombohedral space group R3 with lattice parameters a = 1585.39(5) pm and c = 1098.77(3) pm at room temperature. The compound consists of cuboctahedral [PtBi6I12]2– clusters and Pb2+ cations in octahedral coordination between trigonal faces of two cuboctahedra, which concatenate them into linear chains. Six weaker Bi···I inter‐cluster bridges per cluster connect the chains. The structure can be interpreted as a superstructure of the NaCl structure type, with iodide and platinum(–II) as anions and bismuth(II) and lead(II) as cations, leaving 18 out of 39 cation positions unoccupied. The arrangement of the cuboctahedral clusters follows the motif of a body‐centered cubic packing. Pb[PtBi6I12] is a semiconductor with a measured bandgap of 0.69 eV. Full‐relativistic DFT calculations indicate a topologically trivial bandgap of 0.58 eV.

Rare-earth metal sesquioxides (RE2O3) are stable compounds that require high activation energies in solid-state reactions or strong acids for dissolution in aqueous media. Alternatively, dissolution and downstream chemistry of RE2O3 have been achieved with ionic liquids (ILs), but typically with additional water. In contrast, the anhydrous IL 1-butyl-3-methylimidazolium acetate [BMIm][OAc] dissolves RE2O3 for RE = La–Ho and forms homoleptic dinuclear metal complexes that crystallize as [BMIm]2[RE2(OAc)8] salts. Chloride ions promote the dissolution without being included in the compounds. Since the lattice energy of RE2O3 increases with decreasing size of the RE3+ cation, Ho2O3 dissolves very slowly, while the sesquioxides with even smaller cations appear to be inert under the applied conditions. The Sm and Eu complex salts show blue and red photoluminescence and Van Vleck paramagnetism. The proton source for the dissolution is the imidazolium cation. Abstraction of the acidic proton at the C2-atom yields an N-heterocyclic carbene (imidazole-2-ylidene). The IL can be regenerated by subsequent reaction with acetic acid. In the overall process, RE2O3 is dissolved by anhydrous acetic acid, a reaction that does not proceed directly.

Investigations into potential topological materials yielded the new subiodide Sn[PtBi6I12]. The combination of thermal analyses with phase analyses of the products of isothermal ex situ syntheses allowed the establishment of a complex high‐temperature synthesis protocol for the crystal growth of the target phase despite the lack of knowledge of the quaternary phase diagram. A special challenge was to prevent the formation of competing compounds of the solid solution series (Bi2xSn1–3x)[PtBi6I12] with x≠0. Sn[PtBi6I12] crystallizes, isostructural to Pb[PtBi6I12], in the rhombohedral space group Rtrue3‾ with lattice parameters a=1583.2(2) pm and c=1089.70(10) pm. The compound consists of cuboctahedral [PtBi6I12]2− clusters and Sn2+ cations in an octahedral coordination between the trigonal faces of two cluster units, thereby concatenating them into infinite linear chains. The chains are connected via Bi⋯ I inter‐cluster bridges, creating a high‐entropy variant of the NaCl structure type. Sn[PtBi6I12] is a semiconductor with an experimental bandgap of 0.8(1) eV. Fully relativistic density functional theory calculations including an implementation of the bifunctional formalism for the exchange energy indicate a topologically trivial bandgap of 0.81 eV between bands that are dominated by contributions of bismuth and iodine.