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For the synthesis of metalloid cluster compounds of tin applying the disproportionation reaction of subvalent metastable Sn(I) halides, Si(SiMe3)3 proved to be the ligand with the highest synthetic potential. However, degradation of the Si(SiMe3)3 ligand can also lead to cluster enlargement where additional silicon atoms are incorporated into the cluster core. Here we describe the structure and bonding of the novel anionic cluster compound {Sn10Si(SiMe3)2[Si(SiMe3)3]4}2- 5, where such a degradation has taken place. Additionally, requirements for the formation of 5 are discussed.

We report the synthesis and characterization of ionic compounds [(thf)4YbI]2[Ge9(Hyp)3]2 (1) and [(thf)5LnI]4[Ge9(Hyp)3]4 (Ln = Eu (2), Sm (3)), (Hyp = Si(SiMe3)3). All compounds were examined by UV-Vis spectroscopy and a blue luminescence of Eu2+ was found. The solid state magnetic measurements of complexes 2 and 3 confirmed the presence of divalent lanthanides. [ABSTRACT FROM AUTHOR]

We present a series of new intermetalloid clusters (R3P)CuGe9((Hyp)3, (R=Me, Et, iPr, nBu, tBu) (Hyp=Si(SiMe3)3) (R3P)AuGe9(Hyp)3MGe9(Hyp)3 (R=Ph, Me; M=Au, Cu). In conjunction with already known clusters, these give new insights into the bonding situation of metal bridged Ge9 clusters as well as a better understanding of the formation of these clusters. Additionally, the intermetalloid clusters with the smallest phosphine PMe3 show new bonding motives. [ABSTRACT FROM AUTHOR]

Within the reaction of a metastable Ge(I)Cl solution and Na2Fe2(CO)8 the anionic cubic cluster compound {(thf)14Na6Ge8[Fe(CO)4]8}− (3) is obtained. The open shell character of 3 is proven by EPR spectroscopy. Quantum chemical calculations furthermore show that also the closed shell systems should be stable, but could not be isolated so far. Additionally, 3 can be seen as an intermediate cluster compound on the formation of metalloid clusters. [ABSTRACT FROM AUTHOR]

We report the synthesis, structure and magnetic properties of the first rare earth complexes of metalloid group 14 clusters [(thf)2Ln(Ge9Hyp3)2] (Ln = Eu, Sm, Hyp = Si(SiMe3)3). X-Ray crystallographic analysis and DFT calculations reveal a novel η2-coordination mode of the Ge9Hyp3 units and a slight distortion of the Ge9 cage. [ABSTRACT FROM AUTHOR]

The reaction of GeCl2·dioxane with LiEC(SiMe3)3 (E = Se, Te) shows unexpected products different from those of the previously presented reaction system GeCl2·dioxane/LiSC(SiMe3)3. Here, LiEC(SiMe3)3 (E = Se, Te) acts as a chalcogen atom donor and simultaneously as a substituent to give cage compounds of the composition [(RxGey)Ez] with unique structural features of the Ge/E cores. The molecular structures are presented together with a possible formation mechanism of the selenium/germanium cage compound [{((SiMe3)3CGe)2GeSe4}2(μ2-Se)2] supported by quantum chemical calculations. [ABSTRACT FROM AUTHOR]

The reaction of Et3PAuCl with NaBH4 in EtOH leads to the metalloid gold cluster Au32(Et3P)12Cl8 (Au32) or Au54(Et3P)18Cl12 (Au54) depending on the work-up procedure of the reaction mixture. The molecular structure of Au54 is determined by X-ray diffraction and can be described as a fusion of two Au32 clusters showing a similar solubility. The metalloid cluster Au54 can be either described by a shell model or as a combination of tetrahedral Au4X units (X = Cl, Et3P); edge and face sharing, whereas tetrahedral Au4 units are a central motif in gold cluster chemistry. This novel Au54 gold cluster gives another unique insight into the formation or decomposition process of metalloid clusters, indicating that Au32 and Au54 form from a single yet unknown cluster source. [ABSTRACT FROM AUTHOR]

The reduction of (nBu3P)AgCl with LiBH(sBu)3 in toluene gives the metalloid silver cluster Ag64(PnBu3)16Cl6 (1) as dark red, temperature‐ and light‐sensitive single crystals in high yield. 1 is the largest structurally characterized metalloid silver cluster exhibiting chlorine and phosphine substituents only. The silver atoms in 1 show an overall brick‐shape arrangement, where structural resemblance to the close‐packed fcc and hcp structures is realized. Within 1 a 58 electron closed shell system is present. The light sensitivity renders 1 as a model compound for the primary seeds of the photo process, whereby this sensitivity, together with the high‐yield synthesis show that 1 is a perfect starting compound for further investigations like silver‐plating processes. [ABSTRACT FROM AUTHOR]

Die Reduktion von (nBu3P)AgCl mit LiBH(sBu)3 in Toluol führt zur Bildung des metalloiden Silberclusters Ag64(PnBu3)16Cl6 (1) in Form dunkelroter, wärme‐ und lichtempfindlicher Kristalle in hohen Ausbeuten. 1 ist der größte strukturell charakterisierte metalloide Silbercluster, der nur Chlor‐ und Phosphansubstituenten aufweist. Die Silberatome in 1 sind quaderförmig angeordnet, wobei Ähnlichkeiten zu den dichtesten Kugelpackungen (fcc und hcp) auftreten. In 1 ist ein Schalenabschluss mit 58 Elektronen realisiert. Die Lichtempfindlichkeit macht 1 zu einer Modellverbindung der ersten Schritte des Fotoprozesses. Durch diese Empfindlichkeit im Zusammenspiel mit hohen Ausbeuten ist 1 ein gutes Ausgangsmaterial für weitere Untersuchungen für Silberbeschichtungen. [ABSTRACT FROM AUTHOR]

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The reduction of (nBu3P)AgCl with LiBH(sBu)3 in toluene gives the metalloid silver cluster Ag64(PnBu3)16Cl6 (1) as dark red, temperature‐ and light‐sensitive single crystals in high yield. 1 is the largest structurally characterized metalloid silver cluster exhibiting chlorine and phosphine substituents only. The silver atoms in 1 show an overall brick‐shape arrangement, where structural resemblance to the close‐packed fcc and hcp structures is realized. Within 1 a 58 electron closed shell system is present. The light sensitivity renders 1 as a model compound for the primary seeds of the photo process, whereby this sensitivity, together with the high‐yield synthesis show that 1 is a perfect starting compound for further investigations like silver‐plating processes. [ABSTRACT FROM AUTHOR]

The reaction of GeCl2·dioxane with the sodium salts NaMCp(CO)3 (M = Cr, Mo, W) leads to new four‐membered ring compounds Ge4Cl4[MCp(CO)3]4, where the remaining chlorine atom cannot be substituted by another MCp(CO)3 substituent. A large excess of the sodium salts only leads to some minor side‐reactions. All Ge4‐compounds exhibit a non‐planar four‐membered Ge4 ring, which can be traced back to electrostatic effects as shown by quantum chemical calculations. Furthermore, cluster build‐up reactions might be possible due to the halide substituents in the new ring compounds of germanium, showing that GeCl2·dioxane is an excellent starting material for the synthesis of cluster compounds of germanium. [ABSTRACT FROM AUTHOR]