![]() Some exemplary results with excellent performance are given. The equation can be used at higher pressures and up to the critical point with additional pressure-dependent parameters without changing the basic parameters. Comparison with the newly proposed scaling methods, based on equations containing volume and temperature that were first developed by Andrade in 1934, shows that pressure is absolutely essential as an independent variable. The equation is in no case significantly worse and in most cases superior to the well-known equations of Vogel-Fulcher-Tamman (VFT), Doolittle, Avramov and MCT as well as the recently developed equations which do not contain a singularity above absolute zero. The parameter Vg corresponds above Tm to the limiting value Vg l, below Tm equals Vg 0, the specific volume at the time-and history-independent glass transition temperature Tg 0. For simple liquids above Tm, one parameter is remarkably equivalent to the viscosity at the critical point. The equation applies to liquids above and below the melting point Tm, for super-cooled liquids with modified parameters. Based on the new model of molecular translation in liquids (see Part I), an equation has been formulated based on the finding that relative changes in isobaric viscosity are proportional to the relative change in fractional free volume, leading to an equation with three material-dependent parameters. ![]()
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