Showing papers by "Henry Eyring published in 1969"

Circular dichroism of nucleoside derivatives, vi. the optically active bands of adenine nucleoside derivatives

Abstract: The circular dichroism data on 17 adenine nucleosides show that the 260- and 207-mμ absorption systems of the adenine chromophore each contain at least two electronic transitions. The CD maxima are commonly found at around 260, 220, and 200 mμ, and occasionally at 240 mμ. Solvent studies suggest that these CD bands arise from pi-pi* transitions. A weak absorption band that obeys the McConnell criteria of an n-pi* band is resolved at about 290 mμ in hydrocarbon solvents. This band exhibits very little rotatory power.

Theoretical Calculation of the Pressure Dependence of Liquid Hydrocarbon Viscosities

Abstract: The extension of the significant structure theory of viscosity to the calculation of the viscosities of some selected liquid hydrocarbons such as n‐C12, n‐C15, and n‐C18, etc., has been made. In this derivation, the explicit functional expressions of the molar solidlike volume Vs and the intermolecular potential φ(a) were introduced. The agreement between theory and experiment over a wide temperature (35–135°C) and pressure range (1–3600 bars) is quite satisfactory. The advantage of this treatment is that thermodynamic as well as transport properties are calculated from this same model of the liquid state.

An improved iteration method for the calculation of surface tension using the significant structure theory of liquids.

Abstract: An improved iteration method for calculating the surface tension developed by Chang et al. is presented. To test it, the surface tensions of the following liquids are calculated: A, N2, CH4, PH2, Br2, C6H6, HgCl2, and TiCl4. The calculated results show the present method is an improvement over that of Chang et al. In addition to the change in the energy of sublimation of a molecule in a surface layer, which Chang et al. considered, the less important but not negligible effects on the number of nearest neighbors, ηi, and the characteristic temperature, θi, are now included. ηi is proportional to the effective local density, and θi is proportional to the square root of the effective local density. The calculated values fit the experimental data somewhat more closely than those calculated by the original method of Chang et al.