In present-day chemistry , a carbocation is any positively charged carbon atom , classified in two main categories according to the valence of the charged carbon : three in the carbenium ions ( that can be seen as protonated carbenes , hence the name ) , and five or six in the carbonium ions ( protonated alkanes , named by analogy of ammonium ) .
In present day chemistry , a carbocation is any positively charged carbon atom .