| Citation | Distinguished for his contributions to theoretical chemistry. Originator of the extended Huckel theory. With R.B. Woodward he developed the concept of orbital symmetry conservation, the electronic factors which govern the course of organic chemical reactions. This is held to be one of the most important unifying principles introduced into organic chemistry for several decades. More recently, by considering isolobal relationships between the frontier orbitals of metal ligand fragments and simple organic groups he has built a bridge between inorganic and organic chemistry. This work has allowed rational methods to be developed for preparing organometallic compounds with metal-metal bonds. He has also made several significant contributions to theoretical solid-state chemistry. Roald Hoffmann was awarded the Nobel Prize for Chemistry in 1981. |