Arsenic chloride structures

Formula AsCls MW 181.28 pyramidal structure dipole moment in molecule in the gas phase 1.59 p/D Synonym arsenic (III) chloride arsenic chloride... 

The nickel arsenide structure is the equivalent of the sodium chloride structure in hexagonal close-packing. It can be described as an hep array of arsenic atoms with nickel atoms occupying the octahedral holes. The geometry about the nickel atoms is thus octahedral. This is not the case for arsenic each arsenic atom sits in the centre of a trigonal prism of six nickel atoms (Figure 1.36). 

Inorganic arsenic complexes based on oxygen ligands is scarce. Simple esters of arsenic acid, As(0)(0R)3 (R = Me, Ft, n-Pr, n-Bu, CeHn) have tetragonal structures. Reaction of the diol ligand 2,4-dimethyl-2,4-pentanediol with AsCfr affords an arsenic chloride complex in which the As atom is part of a six-membered ring (37). ... 

Neptunium diarsenide, formed by heating the hydride and arsenic in a sealed tube at ca. 320 for a week, has a powder pattern that indicates a FegAs structure. Heating the compound to 640 °C yields the monoarsenide, with a sodium chloride structure. Both plutonium and americium monoarsenides can be obtained from reactions of the hydride and arsenic at ca. 320 C. 

Dezincification of brasses This may occur, particularly in stagnant or slowly-moving warm or hot waters relatively high in chloride and containing little carbonate hardness. Dezincification of a brasses is inhibited by the usual arsenic addition (see Fig. 4.12), but two-phase brasses are liable to severe attack in some waters . In such waters the use of duplex-structure brass fittings should be avoided. 

The radii in the lowest row of the table were obtained by a number of approximate considerations. For instance, if we assume the bismuth radius to bear the same ratio to the interatomic distance in elementary bismuth as in the case of arsenic and antimony, we obtain (Bi) = 1.16— 1.47 A. A similar conclusion is reached from a study of NiSb and NiBi (with the nickel arsenide structure). Although the structures of the aurous halides have not been determined, it may be pointed out that if they are assumed to be tetrahedral (B3 or Bi) the interatomic distances in the chloride, bromide, and iodide calculated from the observed densities1) are 2.52, 2.66, and 2.75 A, to be compared with 2.19, 2.66, and 2.78 A, respectively, from pur table. 

Lead and Alloys Chemical leads of 99.9 percent purity are used primarily in the chemical industry in environments that form thin, insoluble, and self-repairable protective films, e.g., salts such as sulfates, carbonates, or phosphates. More soluble films such as nitrates, acetates, or chlorides offer little protection. Alloys of antimony, tin, and arsenic offer limited improvement in mechanical properties, but the usefulness of lead is limited primarily because of its poor structural qualities. It has a low melting point and tensile stress as low as 1 MPa (145 Ibf/in ). 

In this section, syntheses of a variety of inorganic nitrogen compounds are described. The syntheses include those of triazanium chlorides alkylamino derivatives of boron, arsenic, and tin and trimeric and tetrameric boron-nitrogen ring structures as exemplified by borazine (HNBH)3. 

Fig. 4. Computer-generated crystal structure models nop row. left to right) Cuprite, zinc-blende, rutile, perovskite. iridymite (second row) Cristobalite. potassium dihydrogen phosphate, diamond, pyrites, arsenic (third rowt Cesium chloride, sodium chloride, wurtzite. copper, niccolite (fourth row) Spinel, graphite, beryllium, carbon dioxide, alpha i uanz. [AT T Bel Laboratories ...

Many studies on the direct reaction of methyl chloride with silicon-copper contact mass and other metal promoters added to the silicon-copper contact mass have focused on the reaction mechanisms.7,8 The reaction rate and the selectivity for dimethyldichlorosilane in this direct synthesis are influenced by metal additives, known as promoters, in low concentration. Aluminum, antimony, arsenic, bismuth, mercury, phosphorus, phosphine compounds34 and their metal complexes,35,36 Zinc,37 39 tin38-40 etc. are known to have beneficial effects as promoters for dimethyldichlorosilane formation.7,8 Promoters are not themselves good catalysts for the direct reaction at temperatures < 350 °C,6,8 but require the presence of copper to be effective. When zinc metal or zinc compounds (0.03-0.75 wt%) were added to silicon-copper contact mass, the reaction rate was potentiated and the selectivity of dimethyldichlorosilane was enhanced further.34 These materials are described as structural promoters because they alter the surface enrichment of silicon, increase the electron density of the surface of the catalyst modify the crystal structure of the copper-silicon solid phase, and affect the absorption of methyl chloride on the catalyst surface and the activation energy for the formation of dimethyldichlorosilane.38,39 Cadmium is also a structural promoter for this reaction, but cadmium presents serious toxicity problems in industrial use on a large scale.41,42 Other metals such as arsenic, mercury, etc. are also restricted because of such toxicity problems. In the direct reaction of methyl chloride, tin in... 

Fe anchored amino-functionalized MCM-41 effectively adsorbs toxic oxyanions, arsenate, chromate, selenate and molybdate, in the aqueous solution. These adsorbents show ones of the largest adsorption capacities reported in the literature. The molar ratio, oxyanion / Fe, is 2.8, 1.8, 1.5 and 2.3, respectively. They are consistent with the coordination mmibers in the EXAFS structural analysis of adsorption complexes. Cr-Fe adsorption centre is uniform, where 2 1 complex is uniformly generated. On the contraiy, chloride ion remains in As- and Se-Fe complexes and two kinds of coordination with different bonding distances were found in As- and Mo-Fe complexes. 

Cyclopentamethylene-t-butylhydroxyarsane bromide 77 has a related ionic structure (As—O 1.729 A) with the six-membered ring in a chair conformation and hydroxy and butyl groups in axial and equatorial positions, respectively . It is curious that hydrolysis of cyclopentamethylenearsenic chloride yields the corresponding dihydroxide, [(CH2)5As(OH)2]C1, with As—O distances of 1.708 and 1.735 A, rather than the, perhaps expected, arsinic acid, (CH2)5As(0)(0H) °. From the As—O separation (1.733 A), it appears likely that an As—OH group is also present in the arsenic sugar sulphate 78, obtained from clam kidneys a related species has also been obtained from algae. ... 

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