Isoelectronic Boron-Nitride Analogous of Fullerenes: A Computational Investigation into Their Thermochemical Properties.

In the present study, we have used computational chemistry to examine the thermochemical properties of fullerene-like caged boron nitride (BnNn) species. For B10N10, there are over 1600 isomers spanning an energy range of over 2500 kJ mol-1. With these isomers, we have determined a linear combination of the number of topological indicators (the different bonds and the different atoms surrounding an atom) that fits well to the atomization energies. Consequently, the coefficients for the indices can be interpreted as the bond energies and the effects of the local atomic environments. The linear formula is also applicable to larger fullerene-like BN species up to B30N30, and we have used the additional species to examine their thermochemical properties. The atomization energies show a converging trend akin to that for the corresponding fullerenes, while the comparison of the ionization energies and electron affinities with those of the bulk material shows that even a relatively small BN cage already approaches bulk properties. This contrasts with the comparison between fullerenes and graphene. The distinct observations highlight the local bonding nature in BN materials versus the delocalized carbon-based materials.