Extracting energy and structure properties of glass-forming liquids from structural relaxation time

Abstract

A comprehensive examination of the kinetic liquid model (Wang et al 2010 J. Phys.: Condens. Matter 22 455104) is carried out by fitting the structural relaxation time of 26 different glass-forming liquids in a wide temperature range, including most of the well-studied materials. Careful analysis of the compiled reported data reveals that experimental inaccuracies should not be overlooked in any 'benchmark test' of relating theories or models (e.g. in Lunkenheimer et al 2010 Phys. Rev. E 81 051504). The procedure, accuracy, ability, and efficiency of the kinetic liquid model are discussed in detail and in comparison with other available fitting methods. In general, the kinetic liquid model could be verified by 17 of the 26 compiled data sets and can serve as a meaningful approximative method for analyzing these liquids. Nonetheless, further experimental examinations in a wide temperature range are needed and are called for. Through fitting, the microscopic details of these liquids are extracted, namely, the enthalpy, entropy, and cooperativity in structural relaxation, which may facilitate further quantitative analysis to both the liquidus and glassy states of these materials.

A relationship between diffusivity and cooperativity of supercooled liquids in the proximity of glass transition

“…The growth behavior of the cooperativity described by this equation is consistent with the results by other studies [30,31]. However, concerning the number of correlated units involved in glassforming liquids, i.e., the number of molecules or structural units that are involved during supercooling depends on theoretical models [31,35]. It would be interesting to perform a _ .…”

Understanding the Role of Cohesive Interaction in Mechanical Behavior of a Glassy Polymer

“…However, the correlation between dynamical heterogeneity and other relaxation parameters such as fragility still remains elusive in condensed matter. , It has been argued that a more fragile glass former with a higher level of packing frustration is expected to exhibit a higher degree of dynamical heterogeneity . On the contrary, several recent studies claim that there is no direct correlation between fragility and cooperativity. − For instance, Hong and co-workers probed the length scale of dynamical heterogeneity (cooperativity) and with fragility via a boson peak, low-frequency vibrational spectrum, where no direct correlation between cooperativity and fragility was found. These contradictory findings raise the question of whether there exists a correlation between dynamical heterogeneity and fragility altered by growing cohesive interaction strength α.…”

Analysis of Cooperativity in Metallic Glass Forming Liquids

“…1 shows the relation between NB and m for different materials evaluated based on the BSCNF model. The numbers of correlated units evaluated by other approaches such as those based on the Donth formula, Nα [6], the four-point correlation functions, Ncorr,4 [7], and the thermodynamic cooperativity discussed by Wang, Nc T [8] To the best of our knowledge, information concerning the number of atoms or size of the regions that move cooperatively in the viscous flow in metallic systems is limited. From this point of view, the BSCNF model is useful, because, once having the values of B and C, we can estimate easily the values of m and NB.…”

“…Concerning the relation between fragility, cooperativity of atomic motions and heterogeneity, some studies have been done [1][2][3][4][5]. In particular, the correlation length of the heterogeneity and the number of molecules involved on it has been evaluated using different approaches [6][7][8]. These studies indicate that no consensus exists regarding the relation between fragility and cooperativity.…”