Spectres VH de la lumière diffusée par le salol liquide et surfondu

Light scattering by transverse waves in supercooled liquids and application to metatoluidine

“…exactly the expression found in the case of Vaucamps et al[10], similar expressions holding now for Γ 12 (t) and Γ 22 (t), though with different signs. These quantities trivially generalize those of equations (5.1).…”

“…This model described successfully a parametrized form of the data obtained by Enright et al [9] in salol, the supercooled liquid which had already been successfully fitted by Vaucamps et al [10]. In Wang's analysis, G 0 is equal to zero as long as the transverse modes do not appear in the spectra and represents the unrenormalized shear modulus at infinite frequency when these modes are visible.…”

“…This method appeared in several papers, the most important being presumably [15,18,19,45]. Wang's first attempt [18] is formally equivalent to the two equations (5.12) which describe the model of Vaucamps et al [10] once the variable Q 3 has been eliminated; indeed, this model may be summarized as follows:…”

“…Let us start by discussing a very simple case which will allow us easily to correlate the many variable technique with the two variable memory function technique used in Section 2. Analyzing salol data over a large temperature range, Vaucamps et al [10] proposed to improve over the original Andersen-Pecora model by (i) ignoring the existence of an intrinsic viscosity of the liquid, and (ii) imposing that the mass current couples to two dynamical variables not directly coupled one with the other; finally, only one of these variables was supposed to couple with light. Using the Andersen-Pecora notations of equation (5.1), one thus obtains the following set of equations:σ…”

“…Several explanations were then proposed (see, e.g. [10][11][12][13][14]), each one introducing some additional internal mode, i.e. adding at least one more equation containing a linear coupling between this new variable, or its time derivative, and the variables already introduced in [6] or [7].…”