Formal Oxidation State versus Partial Charge—A Comment

Abstract
Copper(III) or copper(I)? The interpretation of the copper center in the anionic complex 1 as Cu1 by Snyder in the first issue of this year stimulated a spontaneous reply by Kaupp et al., which is published here with Snyder's response. The question whether the oxidation state in general is a purely formal concept has apparently not yet been answered to the satisfaction of all. equation image