  Thermodynamic multi-component solution solidification approach to
liquid-to-glass transition is proposed and actual mechanisms underlying
vitrification, other than viscous slowdown, are identified. Due to polydisperse
aggregation in liquid state, glass-forming liquids, irrespective of chemical
composition, appear to be mixtures of various quasi-components whose
thermodynamic quantities shall be expressed not in terms of molar
concentrations of actual chemical components, but in terms of relative
concentrations of dominant structural units. Thermodynamically, any
glass-former is expected to behave as multi-component solution and solidify in
continuous temperature range between apparent liquidus and solidus temperatures
that can be identified as glass-transition range. Using extended irreversible
thermodynamics of polydisperse solutions it is demonstrated that upon
quenching, diffusional and Brownian mass transport in such solutions is negated
within heat removal timescale, which results in dynamical arrest of nucleation
and growth in clusters and solid-liquid phase separation. Rapid solution
solidification proceeds via successive cluster freezing in continuous
temperature range, in line with cluster size dispersity, which can be described
in terms of percolation in static polydisperse fractal ensemble where glass
transition temperature naturally emerges as percolation threshold.
Multi-component solution solidification framework is shown to be reconcilable
qualitatively and quantitatively with the Mode Coupling - Random First Order
Transition scenario. Finally, it is demonstrated that liquid-to-glass
transformation is thermodynamic liquid-to-solid phase transition, glassy state
of matter appears to be solid supersaturated solution of defects in otherwise
perfect matrix, and the true equilibrium structure which glass is unable access
is a crystalline one.
