Structure and polarization of atoms and molecules

IN ORDER TO CONSIDER dielectrics from a molecular point of view, it is necessary to explain the actions of dipoles, which are produced throughout the interior of the dielectric.^∗ A dipole is a combination of a positive and negative charge located a short distance apart, as shown in Figure 1. A dipole is characterized by a dipole moment, which is the product of the magnitude of the charge (positive at one end and negative at the other) and the distance between the charges. The electric field at a distance from the dipole resembles the magnetic field of a bar magnet and depends only on the dipole moment, not on the charge or separation independently.