The reagents in classic synthesis are typically molecules, in layer-by-layer deposition they can be chosen from a wide range of materials. While today most of
the multilayer films have been fabricated using mainly electrostatic attraction as the
driving force for multilayer build-up, this is by no means a prerequisite. There are
many other interactions that have successfully been used for multilayer deposition
including: donor/acceptor interactions, hydrogen bridging, adsorption/drying
cycles, covalent bonds, stereocomplex formation or specific recognition.