Effect Of Critical Fluctuations Research Articles

Electron mobility in simple fluids near the critical point

Abstract We consider the effect of critical fluctuations on the transport of thermalized electrons injected into the inert fluids, and make the following predictions: As the critical point is approached the mobility will decrease because of increased scattering by the long-wavelength fluctuations. Near the critical point the electrons will become localized within long-wavelength density fluctuations. The mobility will not fall to zero, however, because the density fluctuations move and decay and the electrons are thus not permanently trapped at a fixed site. We estimate the mobility in this regime to be about four orders of magnitude below that at the onset of localization. One of us (ARB) would like to acknowledge financial support from the Science Research Council.

Transport coefficients near a critical point in multicomponent fluid systems

The effect of critical fluctuations on the transport coefficients occurring in diffusion, heat conduction and their cross-processes is calculated according to the mode-mode coupling theory. The results of the calculation are described by means of a simple physical model. We find that the Griffiths and Wheeler rules for thermodynamic quantities can be generalized to include these transport coefficients. It is shown that the thermal conductivity of a binary mixture is « in general » nondivergent and becomes divergent at an azeotropic critical point where the Onsager kinetic coefficient for diffusion should be nondivergent. The behaviour near other special critical points is also discussed.