Semiempirical calculations of dihydrogenated buckminsterfullerenes, C60H2

The Covalent Chemistry of Higher Fullerenes: C70 and Beyond

“…With C,,, 1,4-addition results in at least one double bond within a five-membered ring; this situation is energetically unfavorable in fullerene structures. [39] However, some of these energetic costs may be compensated by a reduction in steric interactions. Bond reactivities in higher fullerenes can be estimated by considering 71 bond order^ ['^.^^] or the local spheroid curvature,[34.411 which is expressed as pyramidalization angles of the corresponding carbon atoms.…”

Hydrogenation of Fullerene C60: Material Design of Organic Semiconductors by Computation

“…T h e s ei s o m e r sa r en a m e d1-11 in boldface. As predicted by Matsuzawa et al [51] from quantum-chemical calculations, two isomers, 1 from 1,2-addition and 5 from 1,4-addition, have been synthesized [35,39]. Furthermore, isomer 1 has been synthesized by many different methods [52].…”

“…Direct hydrogenation of C 60 was achieved without the use of a catalyst by exposing solid-phase fullerenes to high-pressure hydrogen gas, and many types of C 60 H n (n =2 −18) were identified by laser-desorption Fourier-transform mass spectrometry [50]. Unfortunately, highly hydrogenated fullerenes discussed in this chapter, C 60 [51]. 11 isomers of Figure 5(a) with a small formation energy were selected to consider the possibility of synthesis.…”

“…The ground state of these isomers is the singlet state. Other isomers that are not considered in this chapter have triplet ground states in semiempirical calculations [51]. The initial hydrogen atom of C 60 H 2 is already shown in the figure.…”

Aromaticity under star dust conditions

“…This characteristic has been evaluated by means of magnetic [27,33,35,36], reactivity [27,37] and in terms of energetic criteria [33,[38][39][40]. The Fowler et al [38] reference is particularly relevant for the present case, as these authors used the recourse of an isodesmic reaction.…”