This is one of two articles in this volume concerned with the boranecarborane
structural pattern. In the other (see Williams, this volume,
p. 67) Williams has shown how the pattern reflects the coordination
number preferences of the various atoms involved. The purpose of the
present article is to note some bonding implications of the pattern, and
to show its relevance to a wide range of other compounds, including
metal clusters, metal-hydrocarbon 7~ complexes, and various neutral or
charged hydrocarbons.