Prediction of Isomeric Form and Bond Angles for Covalent Molecules and Ions

An electrostatic model for prediction of bond angles in covalent molecules is extended to molecules and ions whose central atoms are surrounded by five or six valence electron pairs of which at least one pair is a lone pair. The stable isomers are the isomers which provide the lone pair electrons with the maximum possible cone of space adjacent to the central atom. Angular deflections from symmetrical coordination positions in these molecules are in the directions predicted by the model, but the observed deflections are usually less than those expected on the basis of behavior in simpler molecules.