# Free radical vs radical cation

What is the difference between a free radical and a radical cation? Are they different thing or do they mean same?

## 1 Answer

A radical cation is simply a free radical with a positive charge. Similarly a radical anion is a free radical with a negative charge.

In other words, radical cations and radical anions are subsets of the free radicals.

That said, the term free radical itself is not entirely clear cut, as illustrated in this question.