Main group compounds, short bonds

The elusiveness of stable compounds with a triple bond between two group 14 elements (see Section VI.A) makes their synthesis, isolation and characterization one of the holy grails of main-group chemistry. In view of the many experimental failures to produce such compounds, even as short-lived intermediates (except for a few successes, see Section VI.A), theory remains the only reliable source of information. Furthermore, the calculations can be used to develop and test ideas of how to stabilize this group of compounds, hopefully directing experimentalists to their synthesis and isolation. 

The electronic structure of these small molecules could serve as the basis of a full article in another context, and our short summary of trends in MOs (or negative ionization potentials) lacks the depth the topic deserves. However, an understanding of these preliminary considerations is requisite for understanding the trends in structure and bonding observed in main group element-transition metal compounds. 

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