Because electrical parameters are used to calculate various ferroelectric, pyroelectric, and piezoelectric properties, they are defined in Table 4.1. Impedance is the basic electrical parameter used to characterize electronic circuits, components, and materials; it is defined as the ratio of the voltage applied to the device and the resulting current through it. In other words, impedance is the total opposition a circuit offers to the flow of an alternating current (AC) at a given frequency, generally represented as a complex quantity that can be shown graphically. The basic elements that compose electrical impedances are inductance, capacitance, and resistance: L , C , and R , respectively. In the real world, electronic components are not pure resistors, inductors, or capacitors but a... combination of all three.