title: Interaction between hydrogen molecules and metallofullerenes.
abstract: Within first-principles density functional theory, we explore the feasibility of using metallofullerenes as efficient hydrogen storage media. In particular, we systematically investigate the interaction between hydrogen molecules and La encapsulated all-carbon fullerenes, C(n) (20 < or = n < or = 82), focusing on the role of transferred charges between the metal atoms and fullerenes on the affinity of hydrogen molecules to the metallofullerenes. Our calculations show that three electrons are transferred from La atom to fullerene cages, while the induced charges are mostly screened by the fullerene cages. We find the local enhancement of molecular hydrogen affinity to the fullerenes to be sensitively dependent on the local bonding properties, rather than on the global charging effects.
authors.affiliation: Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA. myoon@ornl.gov
authors.forename: Mina
authors.initials: M
authors.lastname: Yoon
authors.forename: Shenyuan
authors.initials: S
authors.lastname: Yang
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Zhang