title: Imogolite nanotubes: stability, electronic, and mechanical properties.
abstract: The aluminosilicate mineral imogolite is composed of single-walled nanotubes with stoichiometry of (HO)(3)Al(2)O(3)SiOH and occurs naturally in soils of volcanic origin. In the present work we study the stability and the electronic and mechanical properties of zigzag and armchair imogolite nanotubes using the density-functional tight-binding method. The (12,0) imogolite tube has the highest stability of all tubes studied here. Uniquely for nanotubes, imogolite has a minimum in the strain energy for the optimum structure. This is in agreement with experimental data, as shown by comparison with the simulated X-ray diffraction spectrum. An analysis of the electronic densities of states shows that all imogolite tubes, independent on their chirality and size, are insulators.
authors.affiliation: Grupo de Pesquisa em Química Inorgânica Teórica, Departamento de Química-ICEx- Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
authors.forename: Luciana
authors.initials: L
authors.lastname: Guimarães
authors.forename: Andrey N
authors.initials: AN
authors.lastname: Enyashin
authors.forename: Johannes
authors.initials: J
authors.lastname: Frenzel
authors.forename: Thomas
authors.initials: T
authors.lastname: Heine
authors.forename: Hélio A
authors.initials: HA
authors.lastname: Duarte
authors.forename: Gotthard
authors.initials: G
authors.lastname: Seifert
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry*; D004583:Electrons; D055595:Mechanical Phenomena; D036103:Nanotechnology; D043942:Nanotubes / Q000737:chemistry*; D011789:Quantum Theory; D055672:Static Electricity; D014961:X-Ray Diffraction
chemical_list: D000538:Aluminum Silicates; C049037:aluminosilicate