Reinterpreting boron bridges: elimination of the non-isomorphicity of the topological versus geometrical picture traditionally presented for the boranes

摘要

Re-examinationof bonding patterns in the boranes, including a redefinition of both hydrogen and boron bridges, is under-taken. In lieu of traditional three-atom-two-electron bonds, hydrogen bridges are reinterpreted as simply the concatenation of two one-electron bridges about a common hydrogen atom. A fusion of two three-atom-three-electron bonds, formed from a hydrogen bridge augmented by a one-electron bridge between the two boron atoms that are hydrogen bridged, is proposed as a replacement for boron bridges. Such a development produces a far greater degree of geometrical simplicity and symmetry in the resultant models than is created by the use of traditional hydrogen and boron bridges. In addition to obviating what we believe is a false picture that implies otherwise identical atoms have different connectivities, our model eliminates major differences between the geometrical vs. topological pictures of the various boranes that have stood unchallenged since the seminal work on these compounds was first formulated, as well as explaining why penta-coordination is prevalent in the boranes.