Supercritical Correlation Length of Carbon Dioxide Along the Critical Isochore

Abstract
Values of the total correlation length have been calculated in the hydrodynamical region by equating the critical part of measured values of the thermal diffusivity to the Kawasaki expression for the diffusivity. These new values of the correlation length are found to agree rather closely in the range 0.1<~ΔT<~10° C with values calculated from (a) angular anisotropy data and (b) static compressibility data, the latter interpreted according to Ornstein-Zernike theory, with a constant direct correlation length R0=4.2 Å.