arenium ions

Cations derived formally by the addition of a hydron or other cationic species to any position of an arene, e.g. C6H7+ , benzenium. The term includes:
  1. Arenium σ-adducts (Wheland intermediates) (which are considered to be intermediates in electrophilic aromatic substitution reactions) and other cyclohexadienyl cations.
  2. Arenium π-adducts, such as:
[σ-adduct (sigma-adduct), π-adduct (pi-adduct)].
See: aryl cations
PAC, 1995, 67, 1307 (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1318
See also:
PAC, 1994, 66, 1077 (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1077