General theoretical analysis of four-connected polyhedral molecules

Abstract

Molecular orbital calculations on four-connected polyhedral molecules have resulted in the following generalisations. Spherical four-connected transition metal carbonyl polyhedra are characterised by 14 n + 2 electrons and their Main Group analogues by 4 n + 2 electrons. Non-spherical four-connected polyhedra have variable electron counts of 14 n to 14 n + 4 (or 4 n to 4 n + 4). These generalisations have been analysed in terms of Stone's Tensor Surface Harmonic Theory. The development of electron counting rules for condensed polyhedra derived from four-connected polyhedral fragments is also described.