Particle-size effect on the percolation and conductivity of dispersed ionic conductors: A random sequential packing model

The particle-size effect on the percolation and conductivity of ionic conductors containing a dispersed second phase is investigated on the generalized random resistor networks model. A random sequential packing model different from the one used by Roman and Yussouff is proposed, and by computer simulations we find that there is a maximum critical particle size above which the second critical concentration pc^'' at which the conductor-insulator transition takes place, will disappear. The first critical concentration pc^' at which the interface percolation transition occurs may also disappear above the critical particle size. The particle-size effect on the conductivity property of the present model is studied with a powerful and efficient Y-{∇} transformation algorithm, and the numerical results are in good agreement with experiment results and previous conclusion. {} 1996 The American Physical Society.