Abstract
Structural data for different carbaboranes, investigated in the solid and gas phases, have been compiled and arranged systematically. The subdivision of bonds into polyhedral and exopolyhedral, proposed previously, is illustrated by additional examples. It is shown that the concept of the coordination number helps to discover the rules governing the variation of the polyhedral C–C and B–C distances. Since this approach proved to be relatively ineffective in relation to B–B bonds, an attempt was made to estimate the influence of electronic factors on these distances on the basis of a modified inductive rule. This has shown that the polyhedral and exopolyhedral C–X and B–X distances in carbaboranes obey different rules.
The bibliography includes 66 references.