title: Shape and complexity at the atomic scale: the case of layered nanomaterials.
abstract: In nature there are numerous layered compounds, some of which could be curved so as to form fascinating nanoshapes with novel properties. Graphite is at present the main example of a very flexible layered structure, which is able to form cylinders (nanotubes) and cages (fullerenes), but there are others. While fullerenes possess positive curvature due to pentagonal rings of carbon, there are other structures which could include heptagonal or higher membered rings. In fact, fullerenes and nanotubes could display negative curvature, thus forming nanomaterials possessing unexpected electronic and mechanical properties. The effect of curvature in other nano-architectures, such as in boron nitride and metal dichalcogenides, is also discussed in this account. Electron irradiation is a tool able to increase the structural complexity of layered materials. In this context, we describe the coalescence of carbon nanotubes and C(60) molecules. The latter results now open up an alternative approach to producing and manipulating novel nanomaterials in the twenty-first century.
authors.affiliation: Advanced Materials Department, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa San José 2055, Lomas 4a sección, 78216 San Luis Potosí, Mexico. h@ipicyt.edu.mx
authors.forename: Humberto
authors.initials: H
authors.lastname: Terrones
authors.forename: Mauricio
authors.initials: M
authors.lastname: Terrones
authors.forename: Florentino
authors.initials: F
authors.lastname: López-Urías
authors.forename: Julio A
authors.initials: JA
authors.lastname: Rodríguez-Manzo
authors.forename: Alan L
authors.initials: AL
authors.lastname: Mackay
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D003460:Crystallization / Q000379:methods* / Q000639:trends; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods / Q000639:trends; D004867:Equipment Design; D037741:Fullerenes / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D046911:Macromolecular Substances; D008968:Molecular Conformation; D036103:Nanotechnology / Q000295:instrumentation* / Q000379:methods* / Q000639:trends; D043942:Nanotubes / Q000737:chemistry / Q000648:ultrastructure; D037742:Nanotubes, Carbon
chemical_list: D001672:Biocompatible Materials; D037741:Fullerenes; D046911:Macromolecular Substances; D037742:Nanotubes, Carbon; D006108:Graphite; C069837:fullerene C60