An oxycation, or oxocation, is an ion with the generic formula (where A represents a chemical element and O represents an oxygen atom). Their names normally end with the suffix "-ium" or "-yl".

Isolable oxycations

[[File:CH3CO+.svg|thumb|Structural details of the acetyl cation.

Oxycation nomenclature

Main group species

  • - example: nitrosyl tetrafluoroborate
  • - example: nitronium tetrafluoroborate
  • - example: chloryl hexafluororuthenate

More complicated oxycations include species like SOF<sub>3</sub><sup>+</sup>. Aluminyl, antimonyl, bismuthyl derivatives more closely resemble the situation for transition metal oxy cations in the sense that they are bonded to many Lewis bases. The cation [Bi<sub>6</sub>(O)<sub>4</sub>(OH)<sub>4</sub>]<sup>6+</sup>, a face-capped octahedral cluster, is one example.

Transition metal species

Many transition compounds that contain an oxo ligand can be viewed as salts of a hypothetical "oxycation." In condensed phase, they are always complexed with strong Lewis bases.

  • Titanium| - example: titanyl sulfate, .
  • - example: vanadyl chloride, VOCl<sub>3</sub>
  • Vanadyl ion| - example: vanadyl phosphate, VO(HPO<sub>4</sub>)
  • CrO<sub>2</sub><sup>2+</sup> - example: chromyl chloride, CrO<sub>2</sub>Cl<sub>2</sub>
  • MoO<sup>3+</sup> - molybdenyl chloride, MoOCl<sub>3</sub>.
  • FeO<sup>2+</sup> - examples include many ferryl intermediates

Actinide species

  • Protactinium|
  • Uranium|, Neptunium|, Plutonium|, Americium|
  • Uranyl|, Neptunium|,

See also

  • Oxyanion
  • List of aqueous ions by element

References