Hiya, Essentially, I would like to 1) model a stack of 2 (or more) dielectrics or electrets such as to show the surface voltage as a result of a known applied AC or DC voltage and charge time. and 2) I`d also like to be able to model the charge accumulation at the material boundary interfaces in the stack over time, given material parameters such as k, resistivity, ect. For , I assume that either a series capacitance model (such as: http://www.phys.uri.edu/gerhard/PHY204/tsl129.pdf ) or a parallel resistor/capacitor model such as in the attached image is best. If anyone could explain which is best or why they`re both bad I`d appreciate it. For , I`m a bit at a loss and would appreciate if anyone could point me in the correct direction. Thanks!