Semi‐empirical prediction of bond lengths and conformations

For a number of cyclic hydrocarbons we compared overlap populations, obtained by applying a Mulliken population analysis to the results of an extended Hückel calculation, with experimental bond lengths. We analysed the effect of a refinement, viz. the introduction of non‐bonded interactions. Further, we discuss the use of orbital energies in predicting relative stabilities of isomers and conformers.