Production and LDMS characterisation of endohedral alkalifullerene films

Metal-Cage Bonding, Molecular Structures and Vibrational Spectra of Endohedral Fullerenes: Bridging Experiment and Theory

“…Importantly, the minimum of the electrostatic potential in C 3− 82 was found in the position where metal resides in M@C 82 as predicted by calculations 72 73 or shown by experimental X-ray diffraction studies. 74 At the same time, it was also found that electrostatic potential inside C 6− 80 has no distinguishable minima, and hence there are no distinct bonding sites for metal atoms or clusters in C 80 -I h (7). This is indeed confirmed by several computational studies of La 2 @C 80 -I h (7) [75][76][77] and Sc 3 N@C 80 -I h (7).…”

“…8(c)). In general, aside from the local transformations, all these cages share the common motif of C 80 -I h (7). Note also that, C 82 -C s (39663), which was recently found in Gd 3 N@C 82 , 46 is closely related to C 84 -C s (51365) and can be obtained from the latter by the removal of two carbon atoms with subsequent pairwise Stone-Wales transformation.…”

“…Figure 11 plots relative energies of the ten lowest energy C 6− 80 isomers and corresponding Sc 3 N@C 80 and Y 3 N@C 80 clusterfullerenes. The lowest energy isomers for C 6− 80 and Sc 3 N@C 80 are I h (7) and D 5h (6), and there is a gap of ca 80 kJ/mol between these two isomers and the gap of ca 120 kJ/mol between D 5h (6) and all other, less stable isomers. Stability order of C 6− 80 and Sc 3 N@C 80 isomers is rather close, but relative energies of "unstable" Sc 3 N@C 80 isomers are somewhat smaller than those in C 6− 80 .…”

“…It was already discussed that exceptional stability of C 6− 80 -I h (7) can be explained by the special distribution of the pentagons, which minimizes the strain of the cage. Certainly, this factor is important for other fullerenes, even though they may be non-IPR, and in this regard it is not surprising that non-IPR isomers retaining significant part of C 80 -I h (7) can compete in stability with IPR isomers.…”

“…The points for I h(7) and D 5h (6) isomers are highlighted in red. The inset shows enlargement of graph in the range of 2n = 80.…”