Ordered, chemically and thermally stable two-dimensional aggregates that are formed spontaneously by the adsorption of surface active molecules to a solid; the spontaneous molecular adsorption brings molecules close enough together and allows for the short-range van der Waals forces to become important.

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Ordered monomolecular film that is spontaneously formed upon immersion of a solid into a solution of an amphifunctional molecule.

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Monomolecular films that form or self-assemble after immersing a substrate into a solution of an active surfactant.

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A two-dimensional film, one molecule thick, covalently assembled at an interface.

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