Stability issues in computational screening of carbon nanostructures: illustrations on La endohedrals
2017
Abstract
Three important stability problems frequently met in calculations of carbon nanostructures are outlined. The three relative-stability issues concern: isomeric carbon clusters, non-isomeric metallofullerenes differing in the number of the encapsulated metal atom yet placed in still isomeric carbon cages, and monometallofullerenes with different metals encapsulated in one selected carbon cage.
The related computational approaches are illustrated with endohedrals based on La and its congeners located in C-72, C-76 and C-80 cages, both IPR (isolated-pentagon rule) and non-IPR ones, evaluated using various DFT treatments. It is also concluded that amongthe La congeners, Ac can produce the second best encapsulation energy, just after La.