view ( Fig. 5a) ordered periodic arrays composed of gold and nickel cylinders are seen throughout the sample. The period and size of the array of nickel and gold cylinders obtained were 200 nm and 100 nm, respectively. The height of the cylinders was determined to be 2 lm from cross-sectional SEM observation. The shape of the cylinders corresponded precisely to that of the anodic porous alumina used as the host material. The enlarged view in Figure 5b revealed that the shape of the gold cylinders formed at unimprinted sites was circular, whereas the shape of the nickel cylinders at the imprinted sites was strained-triangular. The shapes of the cylinders corresponded to those of the pores of the anodic porous alumina shown in Figure 3c.In conclusion, ordered mosaic nanocomposites composed of gold and nickel cylinders were obtained using a sequence of selective penetration of the barrier layer and subsequent metal deposition. In the present process, a large number of variations of the ordered mosaic composite structures are possible by changing the pattern used for imprinting the aluminum. The first deposition process of the guest material can be applied to control the arrangement and density of the deposits in the composites. For example, selective deposition in anodic porous alumina can be used for doping in two-dimensional photonic crystals. [15,16] Selective deposition is also useful for controlling the density of electron emitters using anodic porous alumina templates, where a controlled interval and density are essential for performing effective field emission. [17,18]

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This article reports on the interfacial behavior of large liquid-phase polycyclic aromatic hydrocarbons in pitches that are common precursors to carbon materials. Experiments were conducted to identify preferred angles of molecular orientation ("surface anchoring" states) and to measure contact angles on a variety of well-characterized substrates. The results show that the large disklike polyaromatic molecules exhibit anomalously weak noncovalent interactions with a variety of surfaces, a fact that we attribute to inhibition of dispersion forces due to geometric mismatch at the interface. It is further found that large polyaromatics prefer edge-on molecular orientation at most interfaces, a configuration that preserves internal aromatic π-π bonds at the expense of inhibited π-surface bonds. A theory of π-π bond preservation is proposed to explain many aspects of wetting, adsorption, anchoring, and supramolecular assembly in this important class of compounds, including the formation mechanism for the classic bipolar Brooks-Taylor mesocarbon spheres. The results are used to discuss the mechanisms of structure selection in carbon materials prepared at high and low temperatures. The results are also used to demonstrate a new approach for molecular engineering of carbon that employs anchoring templates to synthesize new materials with preprogrammed patterns of graphene layer orientation.