Spinning assembly model

An even coarser description is attempted in Ginzburg-Landau-type models. These continuum models describe the system configuration in temis of one or several, continuous order parameter fields. These fields are thought to describe the spatial variation of the composition. Similar to spin models, the amphiphilic properties are incorporated into the Flamiltonian by construction. The Flamiltonians are motivated by fiindamental synnnetry and stability criteria and offer a unified view on the general features of self-assembly. The universal, generic behaviour—tlie possible morphologies and effects of fluctuations, for instance—rather than the description of a specific material is the subject of these models. 

The McConnell model can work reasonably well for systems having only dyad contacts with well-aligned spin orbital overlap.152,153 Numerous examples have been described, and will surely continue to be found, since dyad formation is one of the most common exchange motifs between organic radicals. This is probably in part because favorable AFM exchange between spin-paired radicals can be one of the forces to assemble the radicals in a lattice. 

Fig. 12.13. Schematic of the decimation process exploited in the context of the Ising model (adapted from Domb (1996)). Frame (a) shows the spins that are assembled into blocks resulting in the new spin degrees of freedom shown in (b).

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