Symmetric vs. asymmetric linear M-X-M linkages in molecules, polymers, and extended networks. Academic Article uri icon

abstract

  • Linear M-X-M linkages in which X is a nitride, oxide, or halide commonly occur in dimers, square tetramers, one-dimensional polymers, and extended three-dimensional solids. For low d electron counts a second-order Jahn-Teller mixing of metal dand X porbitals favors asymmetric M-XM bridges. M-X bonding works against the distortion. Going to higher d electron counts also favors the symmetrical bridge by filling M-X * levels. For the cyclic [ML4X]4tetramer and L[ML4X] chain, d electron counts greater than two favor a symmetric bridge; for perovskites, dn metals with n 1 are calculated to be symmetric. The extent of M-X bond length alternation can also be decreased by increasing the electronegativity difference between M and X to widen the HOMO-LUMO Gap. 1986, American Chemical Society. All rights reserved.

published proceedings

  • J Am Chem Soc

author list (cited authors)

  • Wheeler, R. A., Whangbo, M. H., Hughbanks, T., Hoffmann, R., Burdett, J. K., & Albright, T. A.

citation count

  • 313

complete list of authors

  • Wheeler, RA||Whangbo, MH||Hughbanks, T||Hoffmann, R||Burdett, JK||Albright, TA

publication date

  • January 1986