Dielectric spectroscopy and dynamics in confinement

There are numerous reasons, such as frequency range and sensitivity, to employ dielectric spectroscopy for investigating how confinement alters the dynamics of liquids, supercooled liquids, or polymers. However, care has to be taken to account for the fact that the sample is a heterogeneous dielectric, i.e. a mixture of the confining matrix material and the liquid filler whose dynamics are of interest. Since dielectric permittivity is not an additive quantity, extracting the dynamics of the filler can be complicated or even impossible, and the Maxwell-Wagner relations will not always solve the problem. Some guidelines on how to interpret dielectric data on confined systems will be presented.