Arsine properties

Both arsonic and arsinic acids give precipitates with many metal ions, a property which has found considerable use in analytical chemistry. Of particular importance are certain a2o dyes (qv) containing both arsonic and sulfonic acid groups which give specific color reactions with a wide variety of transition, lanthanide, and actinide metal ions. One of the best known of these dyes is... 

Arsenic exists as grey, yellow and black forms of differing physical properties and susceptibilities towards atmospheric oxygen. The general chemistry is similar to that of phosphorus but whereas phosphorus is non-metallic, the common form of arsenic is metallic. Traces of arsenides may be present in metallic residues and drosses these may yield highly toxic arsine, ASH3, with water. 

In view of the excellent donor properties of tertiary arsines, it is of interest to inquire whether these cyc/o-polyarsanes can also act as ligands. Indeed, (MeAs)s can displace CO from metal carbonyls to form complexes in which it behaves as a uni-, bi- or triden-tate ligand. For example, direct reaction of (MeAs)5 with M(CO)6 in benzene at 170° (M = Cr, Mo, W) yielded red crystalline compounds [M(CO)3( -As5Me5)] for which the structure... 

Osmium(II) forms no hexaaquo complex and [Os(NH3)g] +, which may possibly be present in potassium/liquid NH3 solutions, is also unstable. [Os(NH3)5N2] and other dinitrogen complexes are known but only ligands with good 7r-acceptor properties, such as CN, bipy, phen, phosphines and arsines, really stabilize Os , and these form complexes similar to their Ru analogues. 

This reaction normally takes place at 700°C and at low pressure ( < 1 Torr). Doping is accomplished by the addition of arsine, diborane, or phosphine. The addition of ozone (O3) to Reaction (6) at atmospheric pressure or sub-atmospheric pressures provides films with excellent properties. H ]... 

Substances with high vapor pressure evaporate rapidly. Those with low vapor pressure evaporate slowly. The impact of vapor pressure on the rate of evaporation makes vapor pressure a very important property in considering the tactical use and duration of effectiveness of chemical agents. A potential chemical agent is valuable for employment when it has a reasonable vapor pressure. One with exceptionally high vapor pressure is of limited use. It vaporizes and dissipates too quickly. Examples are arsine and carbon monoxide. On the other hand, mechanical or thermal means may effectively aerosolize and disseminate solid and liquid agents of very low vapor pressure. Vapor pressure and volatility are related. Translated into volatility, vapor pressure is most understandable and useful. 

Arsine does not have good warning properties. Although it has a distinct odor, it is only detectable at levels higher than acceptable exposure limits. It does not irritate the eyes, respiratory system, or the skin. 

Use a self-contained breathing apparatus (SCBA). Air purifying respirators (APRs) are not recommended for use in an arsine atmosphere because of poor warning properties and the unknown effectiveness of sorbents used in the filters. 

The unusual fluorocarbon ligand geometry reported last year for [(AsMe2-CF2CFHAsMe2)Cr(CO)4] and related compounds are incorrect. The X-ray data and chemical properties of the compounds are better interpreted in terms of a disordered arrangement of molecules with normal geometries and dimensions. The ditertiary arsine chelates (53) have been synthesized by the... 

The work on complexes of metals of other groups with olefinic tertiary phosphines and arsines has until recently been neglected, but it has now become dear that the chelating properties of these ligands are almost as widespread as those of the more well known bis(phosphine) and bis(arsine) ligands, such as diphos and diarsine. 

The phosphine and arsine ligands (tvpp and tvpa) also react (49) with bis cycloocta-1,5, diene-/tjtt dibromodirhodium(I) to give crystalline derivatives (ligand) RhBr. The spectroscopic properties of these compounds, their chloro analogues and the iodo-phosphine analogue indicate a five-coordinate structure of the type shown in Fig. 38 (50). 

Arsine is nonirritating with a garlic-like odor. Warning properties of exposure to hazardous concentrations are inadequate. ... 

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