Noncovalent interactions: A brief account of a long history

The history of noncovalent interactions is outlined, starting with early interpretations of the symmetry of crystals, then with the fast development of coordination chemistry, and of fundamental analyses in the last century. An attempt is made to provide for the practicing scientists who use noncovalent interactions a historical background of the field, paying credit to often forgotten predecessors. A separate section shows that only in the 20th century instrumentation provided a firm basis for the exploration of noncovalent interactions. Selected examples illustrate the early and rather accurate calculations of some noncovalent energies. With the advent of supramolecular chemistry, noncovalent interactions became a mainstream field of science; this allowed further insight into the nature and strength of these seemingly weak forces. Intermolecular interactions in biological systems have also received early attention. As far as possible, exact references are given for the original publications.