Reactions with a Metalloid Tin Cluster {Sn10[Si(SiMe3)3]4}(2-): Ligand Elimination versus Coordination Chemistry.

Chemistry that uses metalloid tin clusters as a start- ing material is of fundamental interest towards understand- ing the reactivity of such compounds. Since we identified {Sn10(Si(SiMe3)3)4} 2� 7 as an ideal candidate for such reactions, we present a further step in the understanding of metalloid tin cluster chemistry. In contrast to germanium chemistry, ligand elimination seems to be a major reaction channel, which leads to the more open metalloid cluster {Sn10(Si(SiMe3)3)3} � 9, in which the Sn core is only shielded by three Si(SiMe3)3 ligands. Compound 9 is obtained through different routes and is crystallised together with two differ- ent countercations. Besides the structural charact…

Structure and Properties of YbZnSn, YbAgSn, and Yb2Pt2Pb

Abstract YbZnSn, YbAgSn, and Yb2Pt2Pb were synthesized by reacting the elements in sealed tantalum tubes in a high-frequency furnace. The structures of YbAgSn and Yb2Pt2Pb were refined from single crystal X-ray data: YbAgPb type, P 6 m2, a=479.2(2) pm, c=1087.3(3) pm, wR2=0.050, BASF=0.34(8), 509 F2 values, 18 variables for YbAgSn and Er2Au2Sn type, a=776.0(1) pm, c=701.8(2) pm, wR2=0.072, 426 F2 values, 18 variables for Yb2Pt2Pb. The lattice constants of YbZnSn are confirmed: NdPtSb type, P63mc, a=464.7(1) pm, c=747.7(2) pm. The stannides YbZnSn and YbAgSn crystallize with superstructures of the AlB2 type. The zinc (silver) and tin atoms form ordered Zn3Sn3 and Ag3Sn3 hexagons, respectivel…

Molybdenum oxide nitrides of the Mo_{2}(O,N,\square)_{5}$ type : on the way to Mo_{2}O_{5}$

Abstract: Blue-colored molybdenum oxide nitrides of the Mo-2(O,N,square)(5) type were synthesized by direct nitridation of commercially available molybdenum trioxide with a mixture of gaseous ammonia and oxygen. Chemical composition, crystal structure, and stability of the obtained and hitherto unknown compounds are studied extensively. The average oxidation state of +5 for molybdenum is proven by Mo K near-edge X-ray absorption spectroscopy; the magnetic behavior is in agreement with compounds exhibiting (MoO6)-O-v units. The new materials are stable up to similar to 773 K in an inert gas atmosphere. At higher temperatures, decomposition is observed. X-ray and neutron powder diffraction, e…

Congratulations to Bernt Krebs

Searching for hexagonal analogues of the half-metallic half-Heusler XYZ compounds

The XYZ half-Heusler crystal structure can conveniently be described as a tetrahedral zinc blende YZ structure which is stuffed by a slightly ionic X species. This description is well suited to understand the electronic structure of semiconducting 8-electron compounds such as LiAlSi (formulated Li$^+$[AlSi]$^-$) or semiconducting 18-electron compounds such as TiCoSb (formulated Ti$^{4+}$[CoSb]$^{4-}$). The basis for this is that [AlSi]$^-$ (with the same electron count as Si$_2$) and [CoSb]$^{4-}$ (the same electron count as GaSb), are both structurally and electronically, zinc-blende semiconductors. The electronic structure of half-metallic ferromagnets in this structure type can then be d…

CCDC 1044696: Experimental Crystal Structure Determination

Related Article: Claudio Schrenk, Birgit Gerke, Rainer Pöttgen, Andre Clayborne, Andreas Schnepf|2015|Chem.-Eur.J.|21|8222|doi:10.1002/chem.201500550

CCDC 1044697: Experimental Crystal Structure Determination

Related Article: Claudio Schrenk, Birgit Gerke, Rainer Pöttgen, Andre Clayborne, Andreas Schnepf|2015|Chem.-Eur.J.|21|8222|doi:10.1002/chem.201500550