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.