Polygonal model for layered inorganic nanotubes

Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. Multiwalled inorganic nanotubes with circular cross sections must have either an incoherent interface or a large amount of strain. However, nanotubes with a polygonal cross section can have a coherent interface with considerably less strain. We present a model for polygonal nanotubes with no defects where the chirality of the nanotube determines the shape of the cross section. Circular and polygonal nanotubes are compared based on their strain energy and interfacial energy. We have used first-principles calcuations to parameterize strain and interfacial energy for TiS 2 nanotubes. These calculations show that the polygonal model is energetically favorable to the circular model when the inner radius is above a critical radius, 6.2 Å for a TiS 2 nanotube with ten layers. These results should provide insight into further investigations of nanotube structure and allow computational studies to more accurately predict nanotube properties.