Self-assembled multilayer formation of an aromatic bifunctional molecule via selective ionic interaction

The formation of self-assembled multilayers of an aromatic bifunctional molecule, 4-carboxythiophenol, in a non-centrosymmetric structure via selective ion incorporation of cadmium ions is demonstrated. It is found from quartz crystal microgravimetry and ellipsometry studies that reasonably compact films of up to 7 monolayers may be deposited by self-assembly after which the film quality deteriorates. Films such as those obtained in this study containing highly polarizable molecules in a non-centrosymmetric structure may have important application in areas such as non-linear optics.