Tags: Chemical Compound, Chemical Substance.
The phosphonium (more obscurely: phosphinium) cation describes polyatomic cations with the chemical formula PR+4. Salts of the parent PH4+ are rarely encountered but this ion is an intermediate in the preparation of the industrially useful tetrakis(hydroxymethyl)phosphonium chloride:PH3 + HCl + 4 CH2O → P(CH2OH)4+Cl-Organic phosphonium salts are common reagents in the laboratory.
