A carbenium ion is a positive ion with the structure RR′R″C+, that is, a chemical species with carbon atom having three covalent bonds, and it bears a +1 formal charge. Carbenium ions are a major subset of carbocations, which is a general term for diamagnetic carbon-based cations. In parallel with carbenium ions is another subset of carbocations, the carbonium ions with the formula R5+. In carbenium ions charge is localized. They are isoelectronic with monoboranes such as B(CH3)3.[2]
^Scholz, Franziska; Himmel, Daniel; Scherer, Harald; Krossing, Ingo (2013). "Superacidic or Not…︁? Synthesis, Characterisation, and Acidity of the Room-Temperature Ionic Liquid [C(CH3)3]+ [Al2Br7]−". Chemistry – A European Journal. 19 (1): 109–116. doi:10.1002/chem.201203260. PMID23180742.
^Thomas H. Lowery; Kathleen Schueller Richardson (1981). Mechanism and Theory in Organic Chemistry, Second Edition. Harper and Rowe. p. 396. ISBN0-06-044083-X.