The use of density functional theory to understand and predict structures and bonding in main group compounds with multiple bonds

Density functional theory (DFT) calculations have been carried out on a number of compounds in which multiple bonds are formed by or between main group elements. The calculated and observed structures agree very well for P-2, P-4, P=C-R, R-P=P-R, As=C-R, R-As=As-R', R-Bi=Bi-R, and R-2-Ge=Ge-R-2 For a recently reported compound alleged to contain a Ga=Ga (triple) bond the calculations point to a different formulation in which there is only a double bond and a significant role for noncovalent interactions.