First-Principles Determination of the Polarizabilities of Carbon Tubules as a Function of Length

Abstract
We use the local-density-approximation to the density-functional theory to determine the axial polarizabilities of fullerene tubules as a function of length and winding topologies. Specifically, we present linear polarizabilities for tubules of composition C12H24, C36H24, C40H20 and C60H24. The size-dependent variation in the dipole-coupled gaps between pairs of occupied and unoccupied levels leads to enhancements in the polarizability per valence electron as the length of the tubule increases. The results are compared to recent densityfunctional based calculations of the linear and nonlinear polarizabilities for fullerene and benzene molecules.