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Is the glass-forming melt in equilibrium state?

 The four convenient states of glass-forming substance are “the stable equilibrium liquid (L), the metastable supercooled liquid (SCL), the unstable nonequilibrium glass (G), and the stable crystal (C)” [1]. If one considers glass as the self-organizing system [2,3] then even glass-forming melt (T>Tm) does not correspond to equilibrium state whose properties depend only on temperature at a given pressure. Using a special method for analysis of the viscosity-temperature data [4,5] the dynamical liquid-liquid transitions (DLLT) are demonstrated for both the true melt (L) and the supercooled liquid (SCL). Each DLLT represents a transition from one viscous pattern to another; there is no a definite pattern ηi(T) at a given temperature range but a set of possible patterns belonging to the attractor characteristic for the substance. Glass (G) structure is formed by the thermally activated bond waves [2,3], which are orientated by information fields [6] existing during solidification. Such a self-organized structure not necessarily relaxes into crystal (C), and the fate of glass is determined by a competition between the translation-type crystalline long-range order and the orientation-type bond wave one.

[1] E.D. Zanotto, J.C. Mauro. The glassy state of matter: its definition and ultimate fate. J. Non-Cryst.Solids 471, 490 (2017).

[2] E.A. Chechetkina. Is there a relation between glass-forming ability and first sharp diffraction peak? J. Phys.: Condens. Matter 7, 3099 (1995).

[3] E.A. Chechetkina. Self-organization in glass: the synergetic chemical bonding approach. J. Optpel. Adv. Mater. 18, 44 (2016).

[4] E.A. Chechetkina. Key distinctions in activation parameters of viscous flow for ‘strong' and ‘fragile' glass-forming liquids. J. Non-Cryst.Solids 201, 146 (1996).

[5] E.A. Chechetkina. Viscous flow as the self-organizing process: Borate glass-forming liquids. In: Borate Glasses, Crystals and Melts (9th Intern. Conf.; Oxford, 2017). P.31.

[6] H. Haken. Information and self-organization (Springer, 2000).