The Electrical Properties of Bulk Homogeneous Phases

In this section we are concerned with the electrical response of solids with a uniform composition. Mass and charge transport in the presence of concentration gradients are discussed in Section 2.1.3. 

On the time scale of interest to electrochemists (i.e. greater than 1 /js) an electric field can interact with a solid in two principal ways. These are, respectively, the reorientation of defects having electric dipole moments (usually complex defects) and the translational motion of charge carriers (usually simple defects such as vacancies, ionic interstitials, and defect electronic species). 

The second type of interaction leads to a purely real (dc) conductivity 7, 

We therefore deal first with the phenomenon of dielectric relaxation in materials with a single time eonstant and an absence of conductivity and later with materials that show long-range conductivity. As we are primarily concerned with developing the eleetrieal analogs of these processes, little consideration is given to the characteristics of individual defects or materials. Similarly, the thermodynamics of the formation of defects, which determines their concentration, is also ignored. 

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