GEOMETRIC DISTORTIONS IN 4-LEGGED PIANO-STOOL CYCLOPENTADIENYL TRANSITION-METAL COMPLEXES Academic Article uri icon

abstract

  • Ab initio calculations with effective core potentials are used to obtain structural parameters of four-legged piano-stool (also viewed as pseudo-square-pyramidal) cyclopentadienyl transition-metal complexes, CpML4nLn (n = 03), where M = Ru, Os, Rh, and Ir, and L, L = PH3, CO, H, SiH3, Cl, Li, and Be. These four-legged piano-stool complexes distort from an ideal pseudo-square-pyramidal geometry in such a way that the two larger L-M-Ct (Ct = centroid of the Cp ligand) angles correspond to trans ligands, as do the two smaller ones. These distortions are explained in terms of a -interaction model that differs considerably from a previous one, which emphasized the M-L -interactions. A rehybridization between [formula omitted] (one of the two nonbonding d orbitals in a pseudo-C4 CpML4 complex) and [formula omitted] ( antiboding with L's) occurs in the process of distortion from pseudo-C4 to C2 symmetry. The result of the rehybridization is a preference for strong covalently -bonding ligands to be coordinated to the transition metal with a small L-M-Ct angle. 1993, American Chemical Society. All rights reserved.

published proceedings

  • ORGANOMETALLICS

author list (cited authors)

  • LIN, Z. Y., & HALL, M. B.

citation count

  • 40

complete list of authors

  • LIN, ZY||HALL, MB

publication date

  • January 1993