A report on the dielectric response of the liquid crystal compounds - heptyl oxy benzylidene butyl aniline and heptyl oxy benzylidene hexyl aniline - in various smectic and nematic phases under an applied biasing dc electric field is presented. It is found that the orientation of the molecule about the applied dc field is governed by the associated dipole, the structural arrangement of the molecules in different smectic or nematic phase and the ionic motion. Comparative study on pure and silver nanoparticles doped compounds reveal the presence of nanoparticles in the system affecting the local molecular arrangement supporting our earlier findings.