Computational Studies of Relative Stabilities of Low-Spin d cis- and trans-[M(en)X] Complexes (M = Co, Rh, Ir): Steric and Electronic Effects in the Context of the Structural Trans Influence.

Computational studies of low spin d cis- and trans-[M(en)X] complexes (M = Co, Rh, Ir) employing multiple model chemistries find that isomer preferences fall into three categories. Complexes where X is largely a σ-donor (H, CH, CF) prefer cis geometries, in keeping with predictions associated with the trans influence series. Complexes where this donor characteristic is augmented by π acceptor behavior (B(CF), BCl, SiCl) evince even greater preference for cis geometries.