Methods of making mesostructured sol-gel silicate thin films containing two different molecules deliberately placed in two different spatially separated regions in a one-step, one-pot preparation are developed and demonstrated. When the structure-directing agent is the surfactant cetyltrimethylammonium bromide, the structure is 2-D hexagonal with lattice spacings between 31.6 and 42.1 angstroms depending on the dopant molecules and their concentrations. The three general strategies that are used to place the molecules are philicity (like dissolves like), bonding, and bifunctionality. These strategies take advantage of the different chemical and physical properties of the regions of the films. These regions are the inorganic silicate framework, the hydrophobic organic interior of the micelles, and the ionic interface between them. Luminescent molecules that possess the physical and chemical properties appropriate for the desired strategies are chosen. Lanthanide and ruthenium complexes with condensable trialkoxysilane groups are incorporated into the silicate framework. 1,4-Naphthoquinone, pyrene, rhodamine 6G and coumarin 540A, and lanthanides with no condensable trialkoxysilanes occupy the hydrophobic core of micelles by virtue of their hydrophobicity. The locations of the molecules are determined by luminescence spectroscopy and by luminescence lifetime measurements. In all cases, the long-range order templated into the thin film is verified by X-ray diffraction. The simultaneous placement of two molecules in the structured film and the maintenance of long-range order require a delicate balance among film preparation methodology, design of the molecules to be incorporated in specific regions, and concentrations of all of the species.

Two surface‐tethered nanomachines have been constructed at a supramolecular level by employing cylinders of the π‐electron deficient tetracationic cyclophane, cyclobis(paraquat‐p‐phenylene) (blue), inside which polyether pistons incorporating π‐electron rich dioxynaphthalene units (red and pink) can be induced to move when reductants are supplied either by chemicals or from a light source with 9‐anthracenecarboxylic acid (yellow) as the photosensitizer and ethylenediaminetetraacetate (green) as a sacrificial reagent.

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The concept of a macroscopic machine can be realized [1] in solution at a supramolecular level in complexes where the self-assembly [2] of the components can be reversed upon quelling temporarily the molecular recognition that exists between the matching components. Thus, a supramolecular machine can be defined as an assembly of two or more molecular components designed to perform mechanical-like motions with respect to each other in response to some energy supplyÐfor example, chemical, electrochemical, or photo-chemicalÐthat can be switched on and off at will. One of the most highly investigated classes of supramolecular machines [1,3] are those based on the complexes known as pseudorotaxanes. [4] The reason for this is that the dethreading and rethreading movements of a thread through the center of a ring are reminiscent of the action of a linear motor. Numerous artificial supramolecular machines, [1] based on pseudorotaxanes, [4] exist that can be induced to undergo coconformational change [5] by chemical, [6] electrochemical, [7] and photochemical [8±10] means. They have been demonstrated [1] to operate efficiently in solution, albeit in an incoherent manner. In order to realize the full potential of these supermolecules in a machine-shop setting, they have to be organized at interfaces [11] or deposited on surfaces [12] so that they can be made to operate in unison. Herein we describe two solid-state supramolecular machines in action: one in which the machines are trapped physically in a rigid, nanoporous, optically transparent matrix, and the other in which[9] a) Single-crystal X-ray experiments were performed on either a Nonius kappaCCD diffractometer (1) or a Bruker SMART1000 CCD diffractometer (2,3) both equipped with an Oxford Cryosystems openflow cryostat (graphite-monochromated Mo Ka radiation, l 0.71073 ). All structures were solved by direct methods [11] and all non-hydrogen atoms were located by using subsequent difference Fourier methods. [12] b) Crystals of 1 were grown by the following procedure: Lanthanum triflate hydrate (0.029 g, 5 Â 10 À5