title: B40cluster stability, reactivity, and its planar structural precursor.
abstract: We report a comprehensive first-principles study of the structural and chemical properties of the recently discovered B40cage. It is found to be highly reactive and can exothermically dimerize, regardless of the orientation, by overcoming a small energy barrier ≃0.06 eV. The energy gap of the system varies widely with the aggregation of the increasing number of B40cages, from 3.14 eV in a single B40, to 1.54 eV in the dimer, to 1.25 eV in the trimer. We also explore a recipe for protecting the B40cage by sheathing it within a carbon shell and identify carbon nanotubes with a radius of ∼6 Å as optimal hosts for an isolated cage. It is demonstrated that B40can be unfolded into a planar 'molecule' that tessellates the plane. The corresponding 2D boron sheet constitutes a structural precursor foldable into this unique boron cage structure of current interest.
authors.affiliation: Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA. biy@rice.edu.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA. biy@rice.edu and State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.
authors.forename: Zhuhua
authors.identifier: http://orcid.org/0000-0001-6406-0959
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA. biy@rice.edu.
authors.forename: Evgeni S
authors.initials: ES
authors.lastname: Penev
authors.affiliation: Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, USA. biy@rice.edu.
authors.forename: Boris I
authors.initials: BI
authors.lastname: Yakobson