Clusters chalcogenides

Trinuclear Molybdenum and Tungsten Cluster Chalcogenides From Solid State to Molecular Materials... 

Fig. 7.1 Idealized structures of the trinuclear cluster chalcogenides M3Q4L9 (type I, (a)) and M3Q7U (type II, (b)).

Boulanger C, Lequir JM (1988) Molybdenum cluster chalcogenide electrochemistry-111. 

Fischer C, Alonso-Vante N, Fiechter S, Tributsch H, Reck G, Schulz W (1992) Structure and photoelectrochemical properties of semiconducting rhenium cluster chalcogenides RegXgBr2 (X = S, Se). J Alloys Compd 178(l-2) 305-314... 

Lover T efa/1997 Electrospray mass spectrometry of thiophenolate-capped clusters of CdS, CdSe and ZnS and cadmium and zinc thiophenolate complexes observation of fragmentation and metal, chalcogenide and ligand exchange processes Inorg. Chem. 36 3711... 

Lower formal oxidation states are stabilized, however, by M-M bonding in ternary chalcogenides such as M MeQn, M4M6Q13 (M = alkali metal M = Re, Tc Q = S, Se) and the recently reported M gMeS. Their structures are all based on the face-capped, octahedral MeXg cluster unit found in Chevrel phases (p. 1018) and in the dihalides of Mo and W... 

Just as, in Group VB, niobium, so, in this Group, molybdenum provides most of the examples of the chalcogenide halides. The occurrence and preparation of such compounds are described in numerous publications. In most cases, they have been obtained as powders, with the composition based on chemical analyses only. The presence of defined, homogeneous phases is, therefore, in many cases doubtful. In addition, some published results are contradictory. A decision is possible where a complete structure analysis has been made. As will be shown later, the formation of metal-metal bonds (so-called clusters), as in the case of niobium, is the most characteristic building-principle. Such clusters... 

Group 6 Metal Chalcogenide Cluster Complexes and Their Relationships to Solid-State Cluster Compounds Taro Saito... 

Solid-state cluster chemistry is dominated by octahedral (M 5L8)L6 and (MsLi2)L units which are the focus of this paper. These two cluster types are different in the way the metal octahedral core is surrounded by the ligands. In (MsLg)L6-type clusters (Fig. 6.1a), typical for molybdenum and rhenium halides, chalcogenides, and chalcohalides, eight innei hgands (L ) cap the octahedron faces and six outer ligands (L ) are located in the apical positions [9]. For metals with a smaller number of valence electrons, the (M6L i2)L -type clusters... 

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