7343. Phosphonium Iodide

Nomenclature

CAS number: 12125-09-6
H4IP; mol wt 161.91.
H 2.49%, I 78.38%, P 19.13%.
PH4I.

Description and references

Prepd by hydrolysis of a mixture of diphosphorus tetraiodide and white phosphorus: Work, Inorg. Synth. 2, 141 (1946). Improved apparatus for its prepn: Beredjick, ibid. 6, 91 (1960).

Properties

Large, transparent, colorless crystals (usually cubes). Tetragonal system. Sublimes at room temp. Store in sealed ampuls in refrigerator. Vapor pressure: 50 mm at 20°; 760 mm at 62.5°. mp 18.5° under its own vapor pressure. Heat of fusion 12,680 cal/mol. Caution: Heat or traces of moisture or alcohol cause decompn into PH3 and HI. Will detonate if heated rapidly.

Use

In the laboratory prepn of phosphine.