Main group chalcogenates

The chemistry and the structures in this report have been organized by the main-group/chalcogen building block units (Fig. 14.1). At the start of 2000, we were beginning to understand aspects of the chemistry of chalcophosphates both as selenophosphates and thiophosphates. The thesis of Dr. Carl Evenson [14] and his subsequent papers discuss the composition phase diagrams of Y,... 

Fig. 14.1 Representations of main group chalcogen polyhedra. In each figure, the main group element (Si, Ge) is darker, and the chalcogen (S, Se,Te) is shown lighter, (a)...

The number of known polycationic compounds of main group elements is far less than that of polyanionic compounds. Examples include the chalcogen cations S]+, S]+, Se]o and Teg that are obtained when the elements react with Lewis acids under oxidizing conditions. The ions S]1, Sc]1 and Te] have a square structure that can be assumed to have a 6n electron system. 

Table 2 Selected chalcogenates of main group elements investigated by X-ray diffraction...

Figure 1.1 Principal features of the periodic table. The International Union of Pure and Applied Chemistry (IUPAC) now recommends Arabic group numbers 1-18 in place of the traditional Roman I—VIII (A and B). Group names include alkali metals (1), alkaline earth metals (2), coinage metals (11), chalcogens (16), and halogens (17). The main groups are often called the s,p block, the transition metals the d, block elements, and the lanthanides and actinides the / block elements, reflecting the electronic shell being filled. (See inside front cover for detailed structure of the periodic table.)...

The number of known polycationic compounds of main group elements is far less than that of polyanionic compounds. Examples include the chalcogen cations S4 , S , Se" ... 

W. S. Sheldrick, Cages and clusters of the chalcogens, in M. Driess and H. Noth (eds.), Molecular Clusters of the Main Group Elements, Wiley-VCH, Weinheim, 2004, pp. 230 15. 

J. Albertsen, Synthesis and characteristics of new chalcogen-rich heterocycles with organoelement compounds of the 4th main group and purification of bisorganic polysulfanes using titanocene chalcogenide chelate complexes. Doctoral Dissertation, Technical University of Berlin, 1993. 

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