I didn't know it until this morning, and now, so do you!
"Innocence" applies to ligands in organometallic complexes involved in oxidation/reduction reactions. Redox reactions in organometallic complexes are generally assumed to involve only the metal center, while the ligand remains uninvolved. But if the ligand is itself capable of participating in oxidation or reduction, the ligand is "non-innocent" or "suspect".
(So what's guilt, in chemical terms? I suppose that's when the ligand simply reacts with the metal center and the complex disintegrates)
~Chara
