Endohedral clusters count as molecular models for intermetallic compounds—a class of compounds in which bonding principles are scarcely understood. Herein we report soluble cluster anions with the highest charges on a single cluster to date. The clusters reflect the close analogy between intermetalloid clusters and corresponding coordination polyhedra in intermetallic compounds. We now establish Raman spectroscopy as a reliable probe to assign for the first time the presence of discrete, endohedrally filled clusters in intermetallic phases. The ternary precursor alloys with nominal compositions “K5Co1.2Ge9” and “K4Ru3Sn7” exhibit characteristic bonding modes originating from metal atoms in the center of polyhedral clusters, thus revealing that filled clusters are present in these alloys. We report also on the structural characterization of [Co@Ge9]5− (1a) and [Ru@Sn9]6− (2a) obtained from solutions of the respective alloys.

K10Ga3Bi6.65 is the first representative in the ternary system A‐Ga‐Bi (A = alkali metal). It contains [Ga3Bi6]9– anions with planar triangular‐coordinated Ga atoms as the main structural feature, accompanied by isolated Bi–Bi dumbbells. Alkali metal cations are counterbalancing the charges and fill the space between the anionic units. According to the Zintl‐Klemm concept charge balance is reached if an almost equal ratio of single and double‐bonded Bi2 dumbbells are present according to (K+)10[Ga3Bi6]9–([Bi‐Bi]4–)1/6([Bi=Bi]2–)1/6.

Endohedrale Cluster gelten als molekulare Modelle für intermetallische Verbindungen – eine Verbindungsklasse mit kaum verstandenen Bindungsprinzipien. Wir berichten hier über lösliche Clusteranionen mit den bisher höchsten Ladungen pro Clustereinheit. Die Cluster zeigen die große Ähnlichkeit zwischen intermetalloiden Clustern und den entsprechenden Koordinationspolyedern in intermetallischen Verbindungen auf. Während bereits viele endohedrale Zintl‐Ionen über Reaktionen in Lösung erhalten wurden, haben wir nun die Raman‐Spektroskopie als eine zuverlässige Sonde für den erstmaligen Nachweis von diskreten endohedral gefüllten Clustern in intermetallischen Phasen etabliert. Die ternären Vorläuferlegierungen der nominellen Zusammensetzungen “K5Co1.2Ge9” und “K4Ru3Sn7” zeigen charakteristische Bindungsmoden, die von Metallatomen im Zentrum polyedrischer Cluster herrühren, was zeigt, dass in diesen Legierungen gefüllte Cluster vorliegen. Außerdem berichten wir über die strukturelle Charakterisierung von [Co@Ge9]5− (1a) und [Ru@Sn9]6− (2a), die aus Lösungen der entsprechenden Legierungen erhalten wurden.

The search for novel ternary intermetallic compounds with specific structures is still a challenge. We found that the two-step synthesis giving a typical alloy in the first step followed by the reaction of this alloy with alkali metals is a promising route. The intermetallic compounds K 12 Pd 0.47 Sn 17 and K 4 RhPb 9 were synthesized by hightemperature reactions of preformed Pd-Sn and Rh-Pb alloys with K acting as "metal scissors" and were characterized by means of single crystal and powder X-ray diffractometry. The salt-like ternary phases K 12 Pd 0.47 Sn 17 and K 4 RhPb 9 contain novel endohedrally filled intermetalloid clusters [Pd@Sn 9 ] 4and [Rh@Pb 9 ] 4-, respectively. The crystal packing of the products corresponds to filled variants of the binary

The structures of the compounds Pr 5 Si 3 and Zr 3 Si 2 were refined on X-ray single-crystal diffraction data. Pr 5 Si 3 crystallizes with the tetragonal structure type Cr 5 B 3 : space group I4/mcm, Pearson symbol tI32, a = 0.7820(1), c = 1.3812(3) nm, Z = 4, R1 = 0.035, wR2 = 0.080 for 287 unique reflections, 16 refined parameters. Zr 3 Si 2 crystallizes with the tetragonal structure type U 3 Si 2 : Pearson symbol tP10, space group P4/mbm, a = 0.7087(1), c = 0.37060(7) nm, Z = 2, R1 = 0.022, wR2 = 0.042 for 114 unique reflections, 12 refined parameters.