Interaction and concerted diffusion of lithium in a (5,5) carbon nanotube

The interaction and diffusion of lithium atoms in a (5,5) carbon nanotube is studied using density-functional theory. The Li-nanotube interaction perpendicular to the tube axis for a single Li inside and outside the tube is calculated and compared with the Li-graphene interaction obtained using the same technique. Both interactions are similar in the repulsive region but exhibit differences in their attractive part. Nevertheless, they can be described using a common parametrization. The Li-Li interaction is calculated as a function of their separation inside the tube. This interaction is similar to a screened repulsive Coulomb potential at small separations. However, at larger separations, the Li-Li interaction does not vanish and shows residual oscillations. This repulsive long-ranged interaction favors concerted diffusion of many Li atoms compared to the independent diffusion of individual Li inside the tube. Disciplines Engineering | Materials Science and Engineering Comments Suggested Citation: M. Khantha, N.A. Cordero, J.A. Alonso, M. Cawkwell and L.A. Girifalco. (2008). "Interaction and concerted diffusion of lithium in a (5,5) carbon nanotube." Physical Review B. 78, 115430. © 2008 The American Physical Society http://dx.doi.org/10.1103/PhysRevB.78.115430. This journal article is available at ScholarlyCommons: http://repository.upenn.edu/mse_papers/199 Interaction and concerted diffusion of lithium in a (5,5) carbon nanotube M. Khantha,1 N. A. Cordero,1,2 J. A. Alonso,3 M. Cawkwell,4 and L. A. Girifalco1 1Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA 2Departamento de Fisica, Universidad de Burgos, E-09001 Burgos, Spain 3Departamento de Fisica Teorica, Atomica y Optica, Universidad de Valladolid, E-47011 Valladolid, Spain 4Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA Received 2 July 2008; revised manuscript received 19 August 2008; published 25 September 2008 The interaction and diffusion of lithium atoms in a 5,5 carbon nanotube is studied using density-functional theory. The Li-nanotube interaction perpendicular to the tube axis for a single Li inside and outside the tube is calculated and compared with the Li-graphene interaction obtained using the same technique. Both interactions are similar in the repulsive region but exhibit differences in their attractive part. Nevertheless, they can be described using a common parametrization. The Li-Li interaction is calculated as a function of their separation inside the tube. This interaction is similar to a screened repulsive Coulomb potential at small separations. However, at larger separations, the Li-Li interaction does not vanish and shows residual oscillations. This repulsive long-ranged interaction favors concerted diffusion of many Li atoms compared to the independent diffusion of individual Li inside the tube. DOI: 10.1103/PhysRevB.78.115430 PACS number s : 71.20.Tx, 68.43. h, 71.15.Mb