General Molecular Assembly Strategy

Of the many techniques available to the NMR spectroscopist in structural elucidations, none is so valuable as the indirect chemical-shift correlation experiment, such as HMBC, TOCSY (both homo- and heteronuclear varieties), and FLOCK. Once molecular fragments have been identified by the COSY and HSQC experiments, the spectroscopist attempts to combine these fragments by means of the preceding techniques. As indispensable as these methods have become to NMR spectroscopists, they nonetheless suffer a common 

Designation of Carbons Chemical Shift Longer Range Attached Hydrogens 

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The most simple kind of photosynthetic model systems consists of a chromophore linked to an electron acceptor or donor. For example, the porphyrinquinone diad 1 represents a model of the primary [32] photosynthetic reaction center. Various diads have been synthesized and their photophysical properties have recently been reviewed [33]. The general strategy of multistep ET in triad and multifunctionalized molecular assemblies provides a useful means for maximizing the quantum yields of charge-separated states and the lifetime of the redox intermediate states. Evidently, various molecular assemblies following this strategy have been exploited. 

General Aspects Organic monolayers on well-defined metal substrates may be obtained in various ways. Typical strategies are molecular beam epitaxy (MBE) [436], so-called self-assembled monolayers (SAM) [437] or LB films (LB) [438, 439]. SAM s are molecular assemblies formed by the spontaneous interaction of a surfactant with a solid or liquid substrate. Examples are thiols on gold or silver [437,440,441] as well as alkyl-trichlorosilanes on oxide surfaces [442]. 

While in situ assembly strategies described in the previous section are generally preferred for preparing Metal MOF and Polymer MOF composites, template synthesis is the most extensively used strategy for the preparation of MOFs having discrete molecular species encapsulated. The following are two selected examples that serve to illustrate the use of these preparation procedures and their potential. 

Thus, it is herein that we now describe the results of this analysis which we regard as the development of a general strategy for the construction of spherical molecular hosts. [11] We will begin by presenting the idea of self-assembly in the context of spherical hosts and then, after summarizing the Platonic and Archimedean solids, we will provide examples of cubic symmetry-based hosts, from both the laboratory and nature, with structures that conform to these polyhedra. 

Surface science has been one of the first beneficiaries of self-assembled nanostructures (in the form of SAMs). Self-assembly is a very general strategy for forming molecularly tailored interfaces, and, other than the few systems that have formed the basis for the majority of work in SAMs, almost none of the obvious opportunities to use self-assembly to build ordered, nanostructured interfaces have been examined. The preparation of more sophisticated structures based on molecules with complex stmctures, on self-assembled colloids, on multilayered polymers formed by electrostatic interactions between charged groups166,167, or on biologically derived structures is just beginning168-171. 

A number of design strategies to obtain molecular magnets have been proposed [51]. The general idea is to assemble molecules with one or more magnetic centers in such a way that the interactions between the local spins lead to a nonzero spin, always taking advantage of intra- and intermolecular... 

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