Metal‐Halide–Melem Compounds Based on M6‐, M9‐ and M12‐Clusters

M9‐ and M12‐metal clusters appear as face‐sharing double‐clusters in (Pb9Br19)2(Pb1.5Br2)2(melem)3 (6) and as triple‐clusters in (Pb12Br25)4(Pb1.67Br2)3(melem)4 (7). All compounds are characterized by single‐crystal and powder X‐ray diffraction, and further validated by infrared (IR) spectroscopy and 207Pb and 79/81Br NMR studies on (5). Photoluminescence studies on compound (6) reveal emission at 430 nm while the emission of (5) is completely quenched. Solid state reactions between of metal halides with melem are yielding several compounds that are structurally characterized. Octahedral metal (M) clusters M6(halide)12(melem)4, containing a structural motif that may be derived from the firefish, are established together with some related face‐sharing double Pb9‐ and triple Pb12‐clusters and are studied by 79Br NMR and luminescence measurements.The polymerization of melamine is known to result in the formation of melam and melem with increasing temperature. Solid‐state reactions of metal halides with melem (2,6,10‐triamino‐s‐heptazine, C6N7(NH2)3) at approximately 500 °C have formed several melem compounds that are structurally characterized. The isotypic series M6X12(melem)4 is represented by compounds with M=Ca, X=Br (1), M=Sr, X=Br (2), I (3); M=Ba, X=I (4); and M=Pb, X=Br (5). A notable feature in the crystal structures of these compounds is the presence of M6‐metal halide clusters.