Fullerenes thermodynamics

Because the cohesive energy of the fullerene Cyo is —7.29 eV/atom and that of the graphite sheet is —7.44 eV/atom, the toroidal forms (except torus C192) are energetically stable (see Fig. 5). Finite temperature molecular-dynamics simulations show that all tori (except torus Cm2) are thermodynamically stable. 

Solid carbon exists as graphite, diamond, and other phases such as the fullerenes, which have structures related to that of graphite. Graphite is the thermodynamically most stable of these allotropes under ordinary conditions. In this section, we see how the properties of the different allotropes of carbon are related to differences in bonding. 

Dipolar cycloadditions of fullerene C6o to nitrones have been studied. Their mechanism, regiochemistry, and nature of addition have been investigated. All of the reactions lead to the formation of fullerene fused heterocycles. Theoretically, these reactions can lead to four types of additions, such as closed [6,6], open [5,6], closed [5,6], and open [6,6] additions (Scheme 2.317). Energetics and thermodynamic analyses of these reactions show that closed [5,6] and open [6,6]... 

Cationic species of fullerenes have long been considered to be difficult to prepare, based on the well-known resistance of C , toward oxidation. However, reliable methods are now available for the preparation of alkylated fullerene cations RC60+ and RC70+ as long-lived species, allowing their structures and properties to be investigated in detail. Precise evaluation of their thermodynamic stabilities revealed that these cations have stabilities comparable to the terf-butyl cation. 

A. Rojas-Aguilar./i/z Isoperibol Micro-bomb Combustion Calorimeterfor Measurement of the Enthalpy of Combustion. Application to the Study of Fullerene Cgo-J. Chem. Thermodynamics 2002, 34, 1729-1743. 

It is therefore the right time to give a first comprehensive overview of fullerene chemistry, which is the aim of this book. This summary addresses chemists, material scientists and a broad readership in industry and the scientific community. The number of publications in this field meanwhile gains such dimensions that for nonspecialists it is very difficult to obtain a facile access to the topics of interest. In this book, which contains the complete important literature, the reader will find all aspects of fullerene chemistry as well as the properties of fullerene derivatives. After a short description of the discovery of the fullerenes all methods of the production and isolation of the parent fullerenes and endohedrals are discussed in detail (Chapter 1). In this first chapter the mechanism of the fullerene formation, the physical properties, for example the molecular structure, the thermodynamic, electronic and spectroscopic properties as well as solubilities are also summarized. This knowledge is necessary to understand the chemical behavior of the fullerenes. 

Si7o and higher silicon fullerenes, e.g. Si78 and Sis4, are more stable thermodynamically than Sieo because they have a larger number of hexagons and therefore they may be even better candidates for synthesis than Si o61,137. 

The advantage of using antibiotics, cyclodextrins, maltodextrins and fullerenes as chiral selectors is that the enantioselectivity of the molecular interaction takes place in two places inside the cavity (internal enantioselectivity) and outside the cavity—due to the arrangement, size and type of the radicals, atoms or ions bound on the external chain of the chiral selector (external enantioselectivity) [10]. The thermodynamics of the reaction between the enantiomers and chiral selectors plays the main role in the enantioselectivity of molecular interaction. 

Thermodynamic Properties of Fullerene Hydrides C60H2n and Equilibria of Their Reactions... 

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