The observed structure and reactivity in heavy atom analogs of organic compounds challenge our traditional bonding concepts. For example, the heavy atom alkyne analogs prefer a trans-bent structure {figure and additional description to be added} as opposed to the traditional linear structure of carbon based alkynes. Computational quantum chemistry has provided some insight into the bonding in these atypical structures, suggesting that the bond should still be considered a triple bond. However, there are contrary reports indicating that the bond order is considerably less than three. Other heavy atom containing analogs also exhibit deviations from traditional structures.{additional figures and tables to be added} An interesting system is the silicates. Normally they prefer four coordinate structures, but under certain conditions they exhibit five and six coordinate species. Often these occur when organic polyol substituents are present at high pH, which is another interesting observation as earlier reports suggested that organosilicates do not exist.

A common approach to understanding bonding concepts is to vary the substituents attached to the bond of interest and assessing the structural and reactivity changes. From these changes and the known effects of various substituents, the bonding regime and corresponding orbital interactions can be deduced. consequences