Atropoisomer vs. Atropisomer: What's the Difference?

Atropoisomer and Atropisomer Definitions
Atropoisomer
(chemistry) Any of a group of stable molecules differing only in their conformation
Atropisomer
(chemistry) Any conformer that can be isolated as a separate chemical compound and that arises from restricted rotation about a single bond, as in biaryl atropisomers.