Lattices of cubes as phenomenological Maxwell/Maxwell Garnett materials containing large particle interaction

In his treatise 140 years ago James Clerk Maxwell developed a simple and accurate formula for the effective resistivity of conducting sphere lattices provided the particles are widely dispersed and have little mutual interaction. Today this formula is commonly called the Maxwell Garnett (MG) equation. In this paper we demonstrate through both numerical simulation and measurement that there exists a class of complex composite materials that exhibit effective material behavior very nearly predicted by the simple MG equation. This behavior exists even though there can be very large mutual interaction between particles.