Hydrides chalcogens

Aucar et al demonstrated, by means of a four-component relativistic calculation, that the origin of the diamagnetic contribution to any magnetic molecular property is due to contributions from positronic spinors in calculating the response of the system. Several approximations for the calculation of the DSO term were also investigated. As example, the DSO term for the chalcogen hydrides, XH2 (X = O, S, Se and Te), were calculated. 

There were a considerable number of reports over the period 1990-2004 on polyhedral boron hydride species with exo-chalcogen bonds and the following section is structured in terms of increasing polyhedral size. There were also a few reports on polyhedral carborane species, which are at the end of this section, but there were no reports on other heteroborane species with exo-chalcogen bonds. 

Reaction of Group 14 Metal Hydrides with Chalcogen Sources... 

For chalcogenide thin films it is possible to use elemental S, Se, Te as precursors provided that the other source is a volatile and reactive metal. ZnS deposition using elemental zinc and sulphur was the first ALD process developed [4]. Therefore for precursors other than metals, the reactivity of elemental chalcogens is not sufficient. For other precursor types, including halides, 6-diketonates and organometalHcs, simple hydrides, such as H2S, H2Se and H2Te, have typically been used as a second precursor. 

The chalcogenides are synthesized either by reaction of the chalcogen vapour with the actinide metal or the hydride (Faraday-method), or in reaction with compounds ... 

Their hydrides MH3, and trihalides are pyramidal but pentahalides are trigonal bipyramidal Group-16 Elements Chalcogens Increasing Decreasing Exceptions Trends Trends... 

The interaction of the actinides or of their hydrides with chalcogens or H2X, respectively, give a number of nonstoichiometric phases with a composition close to AnX, An2X3, A11X2, An2Xs, or A11X3. Their thermal stability decreases in the order S > Se > Te. The magnetic susceptibility and Mossbauer spectroscopy show that the latter compounds may be formulated as [An +]2(S )2(S-Sf-, [An +]2(S -)3(S-S)2-, and [An +](S2-)(S-S)2-. These compounds have coordination numbers of 8, 10, and... 

Disilyl chalcogen compounds react in a similar manner (eqnation 39), to give both mononuclear complexes and bridged complexes (if excess platinum hydride precursor is used). ... 

Otlium ion (1) A cation (with its counterion) derived by addition of a hydron (hydrogen ion) to a mononuclear parent hydride of the nitrogen, chalcogen, and halogen family, e.g., H4N+ ammonium ion. 

All of the members of the final review team contributed, if not text, then comments to all of the chapters of the book. Their primary responsibilities for the different sections/chapters were divided as follows. Paul Brown prepared the introduction, and the sections on elemental zirconium, the zirconyl ion, the gaseous zirconium oxides, zirconium hydride, the halogen compounds and complexes, the chalcogen compounds and complexes, the Group 15 compounds and complexes, zirconium carbides and silicates. He was assisted by Christian Ekberg in the interpretation of aqueous zirconium complexes in these sections. Some initial work was done by Ken Jackson on the zirconium sulphate, nitrate and phosphate compounds and complexes. Bernd Grambow was responsible for the drafting of the sections on zirconium hydrolysis, the ion and the section on crystalline and amorphous zirconium oxides. Enzo Curti drafted the section on the zirconium carbonates. 

Even though these elements are in the same group as oxygen, they are remarkably different — they are much less electronegative and the hydrides of chalcogen elements other than oxygen, are poisonous gases. 

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