Activation energies and information entropies of helium penetration through fullerene walls. Insights into the formation of endofullerenes nX@C_60/70(n = 1 and 2) from the information entropy approach

Abstract

In the present study, we calculate the activation barriers and information entropies of helium penetration into the C60 and C70 fullerenes resulting in the singly and doubly filled endofullerenes Hen@C60/70 (n = 1 and 2).

Information Entropy in Chemistry: An Overview

“…These are all homonuclear diatomic molecules and rare symmetric species with larger molecular size (Figure 4). Their antipodes with partitions N × 1 are non-symmetric and have the maximal h value for a given N: This approach allows sorting fullerenes [44], endofullerenes [51], oxygen allotropes [45], and interstellar molecules [52] to reveal more and less abundant structures. We performed studies [44,45,51] hypothesizing that a lower possibility of the formation of a chemical structure corresponds to the higher information in the "message" about its formation.…”

“…For example, Zhdanov proposed the classification of natural compounds in the space of two coordinates: h/N and the mean oxidation state of the carbon atoms in the molecule (Figure 5) [57]. The h values were efficient for the rationalization of the formation processes of singly and doubly filled endofullerenes [51]. However, this approach itself was not helpful for understanding addition reactions to fullerenes [58] and 'energy-topology' correlations in isomeric fullerene series [59].…”

Covalently Bonded Fullerene Nano-Aggregates (C60)n: Digitalizing Their Energy–Topology–Symmetry

“…The unfavourability of the formation of linear polymers As the topological indices of oligomers (C 60 ) n demonstrate odd-even effects, we compared them with other structural descriptors, i.e., information entropy (h) and rotational symmetry number (σ). The first one is an information theoretic index widely used in theoretical chemistry of fullerenes (for example, it was previously used for the analysis of endofullerene formation [59] and complexity of fullerene graphs [60]). The second one is a characteristic number of symmetry.…”

On Properties of Distance-Based Entropies on Fullerene Graphs

“…Additionally, entropy-based graph measures may relate to non-equilibrium physicochemical processes (see [ 23 , 24 ]). As for fullerenes, there are direct applications of information entropy to rationalizing the processes of fullerene [ 25 ] and endofullerene [ 26 ] formation.…”