The race within supercooled liquids-Relaxation versus crystallization.

Area of Science:

• Condensed matter physics
• Materials science
• Physical chemistry

Background:

• Supercooled liquids are a key area of study in condensed matter physics and materials science.
• A long-standing question is whether liquids can be cooled below their melting point to the Kauzmann temperature (T_K) without crystallizing or vitrifying.

Purpose of the Study:

• To estimate the kinetic spinodal temperature (T_KS) and Kauzmann temperature (T_K) for selected borate and silicate glass-forming systems.
• To determine if the Kauzmann temperature can be reached in real supercooled liquids.

Main Methods:

• Utilized thermodynamic and kinetic data with established theoretical models.
• Estimated T_KS and T_K for borate and silicate compositions exhibiting measurable homogeneous crystal nucleation.
• Compared T_KS and T_K to understand the fate of supercooled liquids.

Main Results:

• For both studied oxide glass-formers, the kinetic spinodal temperature (T_KS) was found to be significantly higher than the Kauzmann temperature (T_K).
• Crystallization was observed to occur before reaching T_K at deep supercoolings under ambient pressure.
• The predicted entropy catastrophe at T_K is averted by incipient crystal nucleation.

Conclusions:

• The Kauzmann temperature is not reachable for the studied borate and silicate glasses at ambient pressure.
• Homogeneous nucleation of crystals prevents supercooled liquids from reaching the theoretical T_K.
• Findings align with previous computer simulations for silica glass, suggesting T_KS > T_K is a general phenomenon for glasses.