Ditungsten

Ditungsten trisiUcide [12138-30-6], W2Si2, gray in color and having an sp gr of 10.9, is insoluble in water, acid, or alkaline solutions. It is readily attacked by HNO —HE and fused alkah-metal carbonates and hydroxides. 

Prospects for dinuclear transition metal chemistry illustrated by recent advances in the chemistry of dimolybdenum and ditungsten. M. H. Chisholm, Transition Met. Chem. (Weinheim, Ger.), 1978, 3, 321-333 (91). 

Monocaesium acetylide and caesium acetylide, lithium acetylide and rubidimn acetylide, tungsten carbide and ditungsten carbide, and zirconium dicarbide all ignite in cold fluorine, while uranium dicarbide ignites in warm fluorine. 

See Tungsten carbide Nitrogen oxides Ditungsten carbide Oxidants... 

W-W distance (2.48A) reflecting the double bond character. Oxidation of 1 by 02, H202, N02 or Ag(I) salts gives dark red complexes (structure ), which are the ditungsten(V) analogs of (W-W dis-... 

A still more dramatic example is given by the saturated decahydride of ditungsten, H5WWH5, which has the formal Lewis-like structure... 

Ditrimethylolpropane, 2 47 physical properties of, 2 48t Ditungsten boride, 25 386 Ditungsten trisilicide, 25 386 Diucardin, molecular formula and structure, 5 162t Diuloses, 4 711 Diuretics, 22 867 Diuril, 5 168... 

Tetrakis(trifluoroacetato)ditungsten(II) is a bright yellow, diamagnetic solid that is highly air sensitive. It is very soluble in diethyl ether, THF, toluene, and dichloromethane and moderately soluble in hexane. The 84.26 MHz 19F NMR spectrum (in C6D6) consists of a single sharp resonance at 5 — 70.1 versus CFC13(<5 0.0). Other spectroscopic data and physicochemical properties are reported in the literature.17... 

Tetrakis(acetato)ditungsten(II) is a very air-sensitive, bright yellow, diamagnetic solid. It is moderately soluble in THF and acetonitrile but solutions in the latter solvent decompose after several hours. The 360 MHz XH NMR spectrum (in THF-d8) consists of a single methyl resonance at S 2.91. The mass spectrum (solid probe, electron impact, 40-70-eV ionizing voltage) shows the parent ion multiplet at m/e 604. Other spectroscopic data and physicochemical properties are described in the literature.8... 

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