Self-diffusion and volumetric measurements for octamethylcyclotetrasiloxane under pressure at 323 K

Abstract

Self-diffusion coefficients have been measured for octamethylcyclotetrasiloxane (OMCTS) up to 58.4 MPa at 323 K and volume ratios have been determined at the same temperature to 81 MPa and fitted to a modified Tait equation. From the density of liquid OMCTS at the freezing pressure at 323 K, an equivalent hard-sphere diameter of 0.777 nm has been estimated and used in a rough hard-sphere interpretation of the diffusion data.