Role of Entropy and Autosolvation in Dimerization and Complexation of C 60

The supramolecular chemistry of bowl-shaped heptazinc metallocavitands templated by Schiff base macrocycles has been investigated. Dimerization thermodynamics were probed by 1H NMR spectroscopy in benzene-d6, toluene-d8, and p-xylene-d10 and revealed the process to be entropy-driven and enthalpy-opposed in each solvent. Trends in the experimentally determined enthalpy and entropy values are related to the thermodynamics of solvent autosolvation, solvent molecules being released from the monomeric metallocavitand cavity into the bulk solvent upon dimerization. The relationship established between experimentally measured dimerization thermodynamics and autosolvation data successfully predicts the absence of dimerization in CH2Cl2 and CHCl3 and was used to estimate the number of solvent molecules interacting with the monomeric metallocavitand in solution. Host–guest interactions between heptazinc metallocavitands and fullerene C60 have also been investigated. Interestingly, metallocavitand-C60 interactions are only observed in solvents that facilitate entropy-driven dimerization suggesting entropy and solvent autosolvation may be important in explaining concave-convex interactions

Property as Institutions for Resources: Lessons from and for IP

The idea of property in land as the paradigm case of property exercises despotic dominion over property thinking. From the perspective of evolving political economy, however, a land-centric model of property makes very little sense. Property institutions coordinate access to resources, and so it is reasonable to expect them to differ in ways that respond to the characteristics of those resources. The debate about whether intellectual property (IP) is property is instructive. IP scholars have pursued the property debate using a conceptual framework derived from common law real property doctrines and organized around the practical and theoretical problems associated with property rights in land, but the resources at the center of debates about the appropriate extent of IP-rightholder control could not be more different from land. Intellectual resources are routinely sliced and diced, aggregated and fractionated, used and reused, in ways that land is not and could not be. This might mean that IP is not property, as some have argued, or it might mean that we have outgrown the monolithic, land-centric model — that in the postindustrial era of wealth production, the cosmology of property can no longer place terra firma at the center. This Article develops an account of property as a set of resource-dependent legal institutions characterized by overlapping sets of family resemblances and then reconsiders the IP question. Property in intellectual goods resembles property in land in some respects, property in natural resources in other respects, property in corporations in others, and property in intangible financial instruments in still others, but also systematically diverges from each of those other forms of property. Legal institutions for IP must accommodate four important points of divergence: the different incentives of creators and intermediaries; the variety of ways in which intellectual goods are produced; the central importance of intermediation within IP ecologies; and the widespread use of licensing to delineate rights and obligations