Guest components surfaces using

RECOGNITION PHENOMENA AT SURFACES USING PHOTOISOMERIZABLE GUEST OR HOST COMPONENTS... 

A different approach towards the incorporation of metal oxide clusters into zeo-litic pores via chemical vapor deposition has been studied extensively by Ozin et al. [236 - 240]. They developed a method denoted as intrazeolite metal carbonyl phototopotaxy . Metal carbonyls are used as precursors to obtain the occluded guest component because of their volatility, fitting molecular dimensions, ease of purification, ready availability, and facile and quantitative conversion to the respective metal oxide materials with minimal contamination by carbon [236, 240]. The metal carbonyl precursors are transformed into the metal oxides by photochemical oxidation. The term phototopotaxy is meant to indicate the similarity of this preparation method to epitactical growth of semiconducting oxide layers on planar surfaces commonly used to form low-dimensional quantum nanostructures for applications in electronic and optical devices [238]. 

The metastable, 2-D packing motif presented by some Pcs adsorbed on Ag(l 11) has also prompted the utilization of such ensembles as templates for the organization of complementary guest molecules such as fullerenes [193] or corannulenes [194], giving rise to the formation of two-component, 2-D architectures. More recently, a similar approach has been used to prepare a surface-supported, three-component system. In fact, the immersion of an Au substrate into a solution containing both a ZnPc and a Zn porphyrin led to the formation of a highly ordered, 2-D arrangement of both Pc and porphyrin which can act as a bimolecular chessboard toward the supramolecular assembly of a third component (i.e., C6o fullerene) which is selectively trapped in the open spaces (Fig. 25) [195],... 

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