Survey of the bonding in several structural types of trinuclear molybdenum and tungsten cluster compounds Academic Article uri icon


  • The bonding within equilateral triangular clusters of molybdenum and tungsten and the bonding of μ-O, μ-O, and μ-Cl to them have been examined by using nonempirical Fenske-Hall calculations. Calculations on the bipyramidal and trigonal-prismatic metal-oxygen “core” species [Mo3(μ3-O)2]8+ and [Mo3(μ-O)6] indicate that both capping and edge bridging cause the movement of charge out of the main metal-metal bonding orbitals, resulting in the occupation of higher lying nonbonding and antibonding metal-metal orbitals. The electronic structure of the pyramidal fragment [Mo3(μ3-O)(μ-O)3]4+ is shown to be dominated by the influence of the three edge-bridging μ-O groups. The ability of the trinuclear framework to accommodate a variable number of electrons has been investigated by comparative calculations on [Mo3(μ3-O)(μ-O)3]4+ and [Mo3(μ3-O)(μ-Cl)3]5+, as representatives of the pyramidal type, with six and eight electrons, respectively. The results presented are consistent with the generally longer M-M bonds in systems containing the M3(μ3-O)2 core relative to those containing the M3(μ3-O)(μ-O)3. © 1982, American Chemical Society. All rights reserved.

author list (cited authors)

  • Bursten, B. E., Cotton, F. A., Hall, M. B., & Najjar, R. C.

citation count

  • 54

publication date

  • January 1982