Connectedness percolation in monodisperse rod systems: clustering effects

A model is presented that examines the impact of local clustering upon the percolation behaviour of interpenetrable rod-like particles. The percolation threshold, as well as percolation and backbone probabilities, are evaluated as functions of the particle aspect ratio and degree of clustering by way of an analogy to a lattice site percolation problem. The formation of local, physically connected cliques of particles is shown to raise the percolation threshold whilst reducing the percolation and backbone fractions for a fixed volume fraction of particles.