4, the parent phosphonium cation.
In chemistry, the term phosphonium (more obscurely: phosphinium) describes polyatomic cations with the chemical formula PR+
4 (where R is a hydrogen or an alkyl, aryl, or halide group). These cations have tetrahedral structures. The salts are generally colorless or take the color of the anions.[1]
- ^ Corbridge, D. E. C. (1995). Phosphorus: An Outline of its Chemistry, Biochemistry, and Technology (5th ed.). Amsterdam: Elsevier. ISBN 978-0-444-89307-9.