Subject phosphides

Phosphorus appears to have a beneficial effect on the growth rate. At sub-critical temperatures it helps to stabilise the carbide, while at temperatures up to about 900°C the presence of the hard phosphide eutectic network restricts the deformation to which the much more ductile matrix would otherwise be subject. Since the phosphide eutectic melts at about 950°C, irons containing appreciable amounts of this constituent should clearly not be exposed to this temperature. 

In the last decade, numerous compounds of these types have been the subject of detailed CVD studies, demonstrating their potential for the deposition of the corresponding binary materials. Most of the work has concentrated on binary nitrides and phosphides, while the deposition of binary MSb films has been studied to a far lesser extent. The lack of potential precursors has been the major problem for the deposition of group 13-antimonide films for many years. Only a very few group 13-Sb compounds have been known until we and Wells established general synthetic pathways as was shown in Sections 2 and 3. Consequently, detailed investigations concerning their potential to serve for the deposition of the desired materials... 

The types of molecules considered in this work are those that have structural or chemical features that are manifestly different than are those of their more common oxidation state counterparts. Because of the breadth of this subject, selected examples are presented to illustrate typical behavior. The properties of the types of compounds containing the elements in more typical oxidation states may be found in the Inorganic and Organometallic sections describing each element or gronp and will not be discussed in this article. Similarly, minerals, metal phosphides, metal carbides, and compounds where the oxidation state of the element is low based on formal electron counting techniques (as in some catenated Catenation group 14 compounds), but that do not result in unusual chemistry, are not included. 

When subjected to high pressure certain phosphides and arsenides of metals of Groups IIIB and IVB adopt either the cubic NaCl structure (InP, InAs) or a tetragonal variant of this structure (GeP, GeAs) shown in Fig. 6.1(c) in which there are bonds of three different lengths and effectively 5-coordination. The compounds of Ge and Sn, with a total of nine valence electrons, are metallic conductors. This property is not a characteristic only of the distorted NaCl structure, for SnP forms both the cubic and tetragonal structures, and both polymorphs exhibit metallic conduction. (IC 1970 9 335 JSSC 1970 1 143.)... 

An interesting combination of incendiary actions is the subject of a German patent which claims thermitic high-temperature reactions between aluminum ( PyroschlifT ) or calcium silicide, with phosphates such as tertiary calcium phosphate as the oxidizer. Since phosphides are the products of reaction, the application of water during Are fighting will cause formation of self-flammable phosphine. It would appear that such secondary action might be more of a nuisance than tactically efficient. 

Metal Carbides and Phosphides. A series of CBCs were prepared by pyrolyzing a mixture of CB and polyfurfuryl alcohol. The resultant CBC was then subjected to various oxidative treatments. After impregnation with Mo precursor, the CBC was carburized to obtain M02C/CBC catalyst. The M02C supported on CBC, possessing a basic character was more active than the one with an acidic surface. The aetivity was determined using thiophene as the model compound in a microreactor at atmospheric pressure of H2. 

Diborane(6) catalyzes the polymerization of imidazole-borane (see Section 2.2.4.3, p. 19), and it forms HBNH when subjected to an a.c. discharge plasma in the presence of NH3 [9, 10]. Boron phosphide, BP, is deposited as single crystal wafers when diborane(6) is thermally decomposed in the presence of PH3 in an H2 atmosphere [11]. Solvent-free diborane(6) reacts with CH3-U(r 5-C5H5)3 via the intermediate (r 3-CH3-BH3)U(r 5-C5H5)3 to form (r 3-BH4)U(r 5-C5H5)3 [12]. 

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