Percolation and critical behaviour of kinetic coefficients

Second-order phase transitions are studied for a two-component system composed of randomly distributed metal and non-metal regions. It is shown that the percolation threshold the effective Hall coefficient is characterised by four critical exponents, while the effective Seebeck coefficient is characterised by three. Relationships between the critical exponents of the electroconductivity and the Hall and Seebeck coefficients are obtained. A rigorous mathematical theorem for the thermopower in critical regions analogous to those for the electroconductivity and Hall effect that the author derived previously are stated. A probability density distribution function for the contributions of the volume fractions to the effective electroconductivity and Hall effect as well as for the contributions of the intercomponent surface S(p) to the thermopower is established. Approximation formulae for these functions are obtained.