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Laser shock Hugoniot data were obtained using ultrafast dynamic ellipsometry (UDE) for both nonideal (ethanol/water solutions with mole percent χ(ethanol) = 0%, 3.4%, 5.4%, 7.5%, 9.7%, 11%, 18%, 33%, 56%, 100%) and ideal liquid mixtures (toluene/fluorobenzene solutions with mole percent χ(toluene) = 0%, 26.0%, 49.1%, 74.9%, 100%). The shock and particle velocities obtained from the UDE data were compared to the universal liquid Hugoniot (ULH) and to literature shock (plate impact) data where available. It was found that the water UDE data fit to a ULH-form equation suggests an intercept of 1.32 km/s, lower than the literature ambient sound speed in water of 1.495 km/s (Mijakovic et al. J. Mol. Liq. 2011, 164, 66-73). Similarly, the ethanol UDE data fit to a ULH-form equation suggests an intercept of 1.45 km/s, which lies above the literature ambient sound speed in ethanol of 1.14 km/s. Both the literature plate impact and UDE Hugoniot data lie below the ULH for water. Likewise, the literature plate impact and UDE Hugoniot data lie above the ULH for ethanol. The UDE Hugoniot data for the mixtures of water and ethanol cross the predictions of the ULH near the same concentration where the sound speed reaches a maximum. In contrast, the UDE data from the ideal liquids and their mixtures are well behaved and agree with ULH predictions across the concentration range. The deviations of the nonideal ethanol/water data from the ULH suggest that complex hydrogen bonding networks in ethanol/water mixtures alter the compressibility of the mixture.

The translational diffusion constants, D, of biphenyl, diphenylacetylene, diphenylbutadiyne, anthracene, pyrene, rubrene, perylene, and coronene have been determined in the n-alkanes using capillary flow techniques. Pyrene and rubrene were also studied in cyclohexane and several of its derivatives. The solutes showed varying degrees of deviation from the Stokes−Einstein (SE) relation (D = kBT/6πηr); the values of the hydrodynamic radius r decrease as the viscosity η increases. The data can be fitted to D/T = A/ηp with p < 1 (p = 1 for the SE relation). The values of p increase as the solute size increases. In the n-alkanes, they range from p = 0.718 ± 0.004 for biphenyl to p = 0.943 ± 0.014 for rubrene; the largest value (p = 0.982 ± 0.019) is found for rubrene in the cyclohexanes. The D values have been compared with reorientational results and molecular dynamics calculations; they have also been fitted to the Doolittle−Cohen−Turnbull free volume equation. A correlation between the p values and the resul...

The translational diffusion constant, D, of dioxygen, O2, has been measured in the odd n-alkanes n-C7H16 to n-C15H32, two branched alkanes (isooctane and squalane), and several cycloalkanes (cycloh...

The translational diffusion constant, D, of dioxygen, O2, has been measured in n-alkane solutions drawn through a microcapillary by reduced pressure. The passage of O2 through the capillary has bee...