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phosphide phos·phide (fŏs'fīd') or phos·phid (-fĭd)
A compound of phosphorus and a more electropositive element or radical.
any of a class of chemical compounds in which phosphorus is combined with a metal. The phosphide ion is P3, and phosphides of almost every metal in the periodic table are known. They exhibit a wide variety of chemical and physical properties. Although there are a number of ways to prepare phosphides, the most general method is to heat stoichiometric amounts of the metal and red phosphorus to high temperature in an inert atmosphere (i.e., one lacking any chemically reactive substances) or in a vacuum. Other methods that can be used include electrolysis reactions, the reaction of a metal (or a metal halide or metal sulfide) with phosphine (PH3), and reduction of a metal phosphate with elemental carbon at an elevated temperature.4Ti + 2PH3 + heat 2Ti2P + 3H2 Ca3(PO4)2 + 8C + heat Ca3P2 + 8CO In some cases, a metal phosphide will react further with additional metal or phosphorus (usually requiring heat) to yield a phosphide of different stoichiometry; for example,4RuP + P4 + heat 4RuP2.