Agostic interaction

The term agostic interaction was first coined in 1983 by Maurice Brookhart and Malcolm LH Green for the intramolecular interaction of C-H bonds with transition metal centers of complexes. Meanwhile, the term is much broader. It refers generally binding interactions between bonding electron pairs and electron-deficient ( Lewis acid ) atoms in complexes or molecular compounds of electropositive elements. Thus, interactions with main-group and 4f elements are called agostic interactions and intermolecular, as well.