Criteria to predict experimentally stable allotropes

(Phys.org)—A group of researchers from France, the U.K. and Florida proposes criteria to determine whether an allotrope is experimentally feasible. They use theoretical carbon allotropes, penta-graphene and Haeckelites, as examples and demonstrate why penta-graphene, contrary to recent research, is not experimentally practical while Haeckelites could be isolated in the presence of charge transfer ions. Their study appears in The Proceedings of the National Academy of Science.