Three new pnicogen–chalcogen polycations were synthesized under specific conditions in the Lewis‐acidic ionic liquids (ILs) [EMIm]X·nAlX3 and [BMIm]X·nAlX3 (X = Cl, Br; [EMIm]: 1‐ethyl‐3‐methylimidazolium, [BMIm]: 1‐butyl‐3‐methylimidazolium) and crystallized as their tetrahalogenidoaluminate salts. Single‐crystal X‐ray diffraction revealed the new polycation [Bi6Te4Br2]4+ in triclinic [Bi6Te4Br2](AlBr4)4 as the reaction product of bismuth, tellurium, and bismuth tribromide. Substitution of the elements with Bi2Te3 yielded the heterocubane [Bi4Te4]4+ in tetragonal [Bi4Te4](AlBr4)4, which crystallizes isotypically to its known chlorine counterpart. The latter is also accessible from ILs. The interactions between cations and anions were evaluated by quantum‐chemical calculations. Bi2S3, which is insoluble in most media, readily dissolves in the employed IL and forms the new augmented heterocubane [Bi3S4AlCl]3+, which crystallizes with the complex anion [S(AlCl3)3]2– as triclinic [Bi3S4AlCl][S(AlCl3)3]AlCl4. Quantum‐chemical calculations support the assignment of elements in this compound. The monoclinic crystal structure of [Sb13Se16](AlCl4)6(Al2Cl7) contains a new member of the small family of pnicogen–chalcogen spiro‐heterocubanes.

Ther eactiono fB i, BiCl 3 ,a nd CuCl in the ionic liquid [BMIm]Cl·4AlCl 3 (BMIm = 1-n-butyl-3-methylimidazolium) at 180 8Cy ieldeda ir-sensitive shiny black crystals of (CuBi 8 ) [

Black Cu2Bi2S3(AlCl4)2 and orange Ag2Bi2S3(AlCl4)2 were synthesized by solvent‐free reaction (polycrystalline powders) as well as in Lewis‐acidic ionic liquids (crystals) at temperatures of 200 °C or lower. X‐ray diffraction on single‐crystals of Cu2Bi2S3(AlCl4)2 revealed two centrosymmetric polytypes: a rhombohedral one, space group R$\bar{3}$c [a = 658.02(3) pm, c = 6794.3(3) pm], with six formula units in the unit cell (6R polytype), and a hexagonal one, space group P63/m [a = 658.71(6) pm, c = 2265.5(3) pm], with two formula units (2H polytype). Ag2Bi2S3(AlCl4)2 is homeotypic and crystallizes in the acentric hexagonal space group P$\bar{3}$2c with a = 691.65(3) pm, c = 2207.86(9) pm, and two formula units per unit cell (2H′ polytype). All structures consist of 2∞[(M+)2Bi2S3] layers (M = Cu, Ag) separated by double layers of AlCl4– tetrahedra and differ mainly in their stacking sequences and the orientation of the AlCl4– groups. The sulfidometalate layer is a honeycomb‐like network with M+ and S2– ions in plane, whereas pairs of Bi3+ cations occupy positions above and below the plane. The analysis of chemical bonding reveals strong covalent two‐center two‐electron bonds in the five‐atomic bipyramidal Bi2S3 unit (D3h symmetry) and covalent bonding with much higher ionic component to the coin metal cations. The DFT‐optimized shape of an isolated hypothetical Bi2S3 molecule differs only marginally from that in the layer. Hence, the compounds might be interpreted as Bi2S3 molecules embedded in MAlCl4 salts. Optical bandgaps of 1.6 eV (M = Cu) and 2.2 eV (M = Ag) were deduced from diffuse reflectance measurements. DFT‐based quantum chemical calculations indicate direct bandgaps of the same magnitude.

The application of ionic liquids for the dissolution of metal oxides is a promising field for the development of more energy‐ and resource‐efficient metallurgical processes. Using such solutions for the production of valuable chemicals or electrochemical metal deposition requires a detailed understanding of the chemical system and the factors influencing it. In the present work, several compounds are reported that crystallize after the dissolution of copper(II) oxide in the ionic liquid [Hbet][NTf2]. Dependent on the initial amount of chloride, the reaction temperature and the purity of the reagent, copper crystallizes in complexes with varying coordination geometries and ligands. Subsequently, the influence of these different complex species on electrochemical properties is shown. For the first time, copper is deposited from the ionic liquid [Hbet][NTf2], giving promising opportunities for more resource‐efficient copper plating. The copper coatings were analyzed by SEM and EDX measurements. Furthermore, a mechanism for the decomposition of [Hbet][NTf2] in the presence of chloride is suggested and supported by experimental evidence.

Bi2S3 was dissolved in the presence of either AuCl/PtCl2 or AgCl in the ionic liquids [BMIm]Cl ⋅ xAlCl3 (BMIm=1‐n‐butyl‐3‐methylimidazolium; x=4–4.3) through annealing the mixtures at 180 or 200 °C. Upon cooling to room temperature, orange, air‐sensitive crystals of [BMIm](Bi4S4)[AlCl4]5 (1) or Ag(Bi7S8)[S(AlCl3)3]2[AlCl4]2 (2) precipitated, respectively. 1 did not form in the absence of AuCl/PtCl2, suggesting an essential role of the metal cations. X‐ray diffraction on single‐crystals of 1 revealed a monoclinic crystal structure that contains (Bi4S4)4+ heterocubanes and [AlCl4]− tetrahedra as well as [BMIm]+ cations. The intercalation of the ionic liquid was confirmed via solid state NMR spectroscopy, revealing unusual coupling behavior. The crystal structure of 2 consists of (Bi7S8)5+ spiro‐dicubanes, [S(AlCl3)3]2− tetrahedra triples, isolated [AlCl4]− tetrahedra, and heavily disordered silver(I) cations. No cation ordering took place in 2 upon slow cooling to 100 K.