Ellegaard Niels L, Christensen Tage, Christiansen Peder Voetmann, Olsen Niels Boye, Pedersen Ulf R, Schrøder Thomas B, Dyre Jeppe C
DNRF Centre Glass and Time, IMFUFA (27), Department of Sciences, Roskilde University, Postbox 260, DK-4000 Roskilde, Denmark.
J Chem Phys. 2007 Feb 21;126(7):074502. doi: 10.1063/1.2434963.
Thermoviscoelastic linear-response functions are calculated from the master equation describing viscous liquid inherent dynamics. From the imaginary parts of the frequency-dependent isobaric specific heat, isothermal compressibility, and isobaric thermal expansion coefficient, we define a "linear dynamic Prigogine-Defay ratio" LambdaTp(omega) with the property that if LambdaTp(omega)=1 at one frequency, then LambdaTp(omega) is unity at all frequencies. This happens if and only if there is a single-order-parameter description of the thermoviscoelastic linear responses via an order parameter (which may be nonexponential in time). Generalizations to other cases of thermodynamic control parameters than temperature and pressure are also presented.
热粘弹性线性响应函数是根据描述粘性液体固有动力学的主方程计算得出的。从与频率相关的等压比热、等温压缩率和等压热膨胀系数的虚部，我们定义了一个“线性动态普里高津 - 德法伊比率”$\Lambda_{Tp}(\omega)$，其性质为如果在某一频率下$\Lambda_{Tp}(\omega)=1$，那么在所有频率下$\Lambda_{Tp}(\omega)$都等于1。当且仅当通过一个序参量（其在时间上可能是非指数形式的）对热粘弹性线性响应存在单序参量描述时，才会出现这种情况。文中还给出了对温度和压力以外的其他热力学控制参数情况的推广。
