Dielectric properties of acetonitrile confined in carbon nanotubes

Abstract

This study addresses numerical investigation of dielectric properties of acetonitrile confined in Single Walled Carbon Nano Tubes (SWCNTs). Frequency dependent permittivity have been computed by assuming whether interactions among the Acetonitrile (ACN) molecules exist or not. Both axial and radial dielectric permittivity show tube diameter dependence. Static dielectric permittivity becomes larger with the diameter of the tubes but still smaller than that of the bulk state as well. Furthermore, an anomalous decrease in radial component of dielectric permittivity was observed. Bending modes and stretching modes between the Carbon atoms affect the variation of dielectric permittivities as well. Moreover, Kirkwood correlation factor, g factor, firmly influenced by the size of the tube and Knudsen region where immediate interactions of ACN molecules start to develop in the this region for narrower tubes too. Both relaxation and reorientation of Acetonitrile inside the CNTs are slower than those of the bulk state. © 2019 Elsevier B.V.