Group 15 elements phosphides

The reduction of phosphates by carbon is a classical method, but the purity of phosphides obtained this way can be suspect. This also holds for replacement reactions, in which a redox process between a transition metal and a metal phosphide is used for the preparation of phosphides with high thermal stabihty. Binary main-group element and transition metal phosphides hke AIP, CrP, NbP, MoP, or WP can be prepared by the reaction of the powdered metals with a melt of hthium metaphosphate LiP03. Bulk samples of transition metal phosphides hke C02P or NiMoP can be obtained via reduction of metal oxide/phosphate mixtures in a mixture of 5% H2 in N2. MoP, WP, Fc2P, M2P, FeP, and RuP can be synthesized by direct reduction of the transition metal phosphates in hydrogen atmosphere between 670 and 1320 K. ... 

ELEMENTS (Metals and intermetallic alloys metalloids and nonmetals carbides, silicides, nitrides, phosphides) l.A Metals and Intermetallic Alloys l.AA. Copper-cupalite family TAB. Zinc-brass family l.AC. Indium-tin family l.AD. Mercury-amalgam family l.AE. Iron-chromium family l.AF. Platinum group elements l.AG. PGE-metal alloys... 

The phosphides and arsenides of the elements M—PRR and M—AsRR are well known for main group elements, but transition metal analogues are more unusual. Insertion reactions were not widely explored until recently, but examples are given in reactions (j) and (k) (X = O or S) ° and (l) (n) (X = or As ) and (m) are effectively oxidative insertions of a nitrene, or specifically PhN into an Sn-P or Sn-As bond, and thus represent an extension of the Staudinger reactions whereby a phosphine or arsine is treated with an azide, and thereby converted into a phosphine-imine or the arsine analogue, as follows ... 

Earlier published reactions of PH3 with organometallic compounds are covered in Phosphor C, 1965, p. 48. A large series of reactions of PH3 with certain organyl-substituted compounds of the main group elements which were claimed to be suitable for the deposition of a variety of films or layers mainly of phosphides on different substrates are covered in Section 1.3.1.6, pp. 293/308. 

Few industrial uses have so far been found for phosphides. Ferrophosphorus is produced on a large scale as a byproduct of P4 manufacture, and its uses have been noted (p. 480). Phosphorus is also much used as an alloying element in iron and steel, and for improving the workability of Cu. Group 3 monophosphides are valuable semiconductors (p. 255) and Ca3P2 is an important ingredient in some navy sea-flares since its reaction with water releases spontaneously flammable... 

Compounds with Sc, Y, lanthanoids and actinoids are of three types. Those with composition ME have the (6-coordinated) NaCl structure, whereas M3E4 (and sometimes M4E3) adopt the body-centred thorium phosphide structure (Th3P4) with 8-coordinated M, and ME2 are like ThAsi in which each Th has 9 As neighbours. Most of these compounds are metallic and those of uranium are magnetically ordered. Full details of the structures and properties of the several hundred other transition metal-Group 15 element compounds fall outside the scope of this treatment, but three particularly important structure types should be mentioned because of their widespread occurrence and relation to other structure types, namely C0AS3,... 

The reaction of the hydrides of both the Groups nib and Vb elements is also used notably in the production of boron phosphide at 950-1000°C as follows ... 

Most nonmetallic elements will react with the group IA and IIA metals to give binary compounds. Heating the metals with nitrogen or phosphorus gives nitrides and phosphides of the metals. 

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