Intrinsic Dielectric Constant Anomaly in Critical Liquid Mixtures

Abstract

Experimental data are presented for the dielectric constant $\ensuremath{\varepsilon}$ near the consolute point of the binary liquid mixture methanol-cyclohexane and that of pseudobinary liquid mixtures of methanol-cyclohexane--deuterated-cyclohexane. One of the methanol-cyclohexane--deuterated-cyclohexane mixtures is made isopycnic at the critical temperature. This has permitted us to investigate more directly the intrinsic critical contribution to $\ensuremath{\varepsilon}$ near the critical point by reducing the contribution resulting from the mass density fluctuations.