Glass transition and rigidity in the aging linear harmonic oscillator model

Flores‐Ruiz, Hugo M.; Naumis, Gerardo G.; Micoulaut, Matthieu

doi:10.1016/j.jnoncrysol.2020.120127

Cited by 5 publications

(2 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…One should search for isostatically rigid structural motifs with dangling ends with varying network connectivities to enhance the width of the IP. Micoulaut was one of the first to recognize the link between the enthalpy of relaxation at T g and the rigidity of glassy networks. , These contributions opened the way for MD simulations to probe rigidity and stress transitions, defining reversibility windows, in binary Ge x Se 100‑ x and (Na 2 O) x (SiO 2 ) 100‑ x glasses. , …”

Section: Discussionmentioning

confidence: 99%

Unusual Role of P–P Bonds on Melt Dynamics and Topological Phases of the Equimolar Ge_xP_xSe_100–2x Glass System

et al. 2020

View full text Add to dashboard Cite

Equimolar Ge x P x Se100–2x ternary glasses have been synthesized over a wide composition range, 4% < x < 25%, and examined in Raman scattering, modulated DSC, and volumetric experiments. Modulated DSC experiments show the enthalpy of relaxation at T g to display a square-well-like reversibility window with an onset (end) of 9.0% (18.0%) respectively, thus, fixing the onset of the rigidity transition, near x r = 9.0% and the stress transition, near x s = 18.0%. These findings show that the Intermediate-Phase (IP) resides in the 9% < x < 18% range. Melt fragility index, m(x) display a Gaussian-like minimum with m(x) < 20 for IP compositions and with m > 20 for non-IP ones. Fragility index results show a global minimum of m = 14 near the center of the window, x = 14, underscoring IP melts to be superstrong. Molar volumes, V m (x), of glasses reveal a Gaussian-like minimum, for IP compositions in relation to the non-IP ones. Melt fragility indices are closely correlated to the glass enthalpy of relaxation, and they show that superstrong melts yield IP glasses, while fragile melts yield flexible phase (FP) or stressed-rigid phase (SRP) glasses upon cooling. Special synthesis of glasses permitted the variance of Ge or P content, ⟨Δx⟩, across 1.5-g-sized batch compositions could be reduced to less than 0.1%. The homogeneous nature of glasses led to abrupt rigidity- and stress-elastic phase transitions in harmony with the percolative nature of these transitions as predicted by theory. Availability of the topological phases (TPs) in Ge x Se100‑x glasses, and P x Se100‑x glasses from earlier work, when combined with the presently measured TPs in the equimolar Ge x P x Se100–2x glasses, has permitted constructing a global TP diagram for the Ge–P–Se composition triangle. The global plot will assist in the choice of appropriate glass compositions for select applications of these materials. In spite of homogenization of these melts/glasses, compositional trends in T g(x) and Raman vibrational modes show that the P–P bearing local structural units of P4Se3 monomers and ethylene-like P2(Se1/2)4 units are decoupled from the network backbone in the IP and in the SRP.

show abstract

Section: Discussionmentioning

confidence: 99%

Unusual Role of P–P Bonds on Melt Dynamics and Topological Phases of the Equimolar Ge_xP_xSe_100–2x Glass System

et al. 2020

View full text Add to dashboard Cite

show abstract

“…A simplified two-level model allows the capturing of such effect in a very crude way [83]. From all these considerations, it is clear that the RK method requires a careful study of the possible structural motifs, in many cases aided by looking at the available melt experimental data [84].…”

mentioning

confidence: 99%

Richard Kerner’s Path Integral Approach Aims to Understand the Self-Organized Matter Agglomeration and Its Translation into the Energy Landscape Kinetics Paradigm

Naumis

2023

Axioms

Self Cite

View full text Add to dashboard Cite

Matter grows and self-assembles to produce complex structures such as virus capsids, carbon fullerenes, proteins, glasses, etc. Due to its complexity, performing pen-and-paper calculations to explain and describe such assemblies is cumbersome. Many years ago, Richard Kerner presented a pen-and-paper path integral approach to understanding self-organized matter. Although this approach successfully addressed many important problems, including the yield of fullerene formation, the glass transition temperature of doped chalcogenide glasses, the fraction of boroxol rings in B2O3 glasses, the first theoretical explanation for the empirical recipe of window and Pyrex glass and the understanding of virus capsid self-assembly, it still is not the primary choice when tackling similar problems. The reason lies in the fact that it diverges from mainstream approaches based on the energy landscape paradigm and non-equilibrium thermodynamics. In this context, a critical review is presented, demonstrating that the Richard Kerner method is, in fact, a clever way to identify relevant configurations. Its equations are simplified common physical sense versions of those found in the energy landscape kinetic equations. Subsequently, the utilization of equilibrium Boltzmann factors in the transition Markov chain probabilities is analyzed within the context of local two-level energy landscape models kinetics. This analysis demonstrates that their use remains valid when the local energy barrier between reaction coordinate states is small compared to the thermal energy. This finding places the Richard Kerner model on par with other more sophisticated methods and, hopefully, will promote its adoption as an initial and useful choice for describing the self-agglomeration of matter.

show abstract

The glass transition as a boundary layer problem of the energy landscape kinetic master equations and its relationship with quantum path integrals

Naumis

2024

Molecular Physics

View full text Add to dashboard Cite

Glass transition and rigidity in the aging linear harmonic oscillator model

Cited by 5 publications

References 45 publications

Unusual Role of P–P Bonds on Melt Dynamics and Topological Phases of the Equimolar Ge_xP_xSe_100–2x Glass System

Unusual Role of P–P Bonds on Melt Dynamics and Topological Phases of the Equimolar Ge_xP_xSe_100–2x Glass System

Richard Kerner’s Path Integral Approach Aims to Understand the Self-Organized Matter Agglomeration and Its Translation into the Energy Landscape Kinetics Paradigm

The glass transition as a boundary layer problem of the energy landscape kinetic master equations and its relationship with quantum path integrals

Contact Info

Product

Resources

About

Glass transition and rigidity in the aging linear harmonic oscillator model

Cited by 5 publications

References 45 publications

Unusual Role of P–P Bonds on Melt Dynamics and Topological Phases of the Equimolar GexPxSe100–2x Glass System

Unusual Role of P–P Bonds on Melt Dynamics and Topological Phases of the Equimolar GexPxSe100–2x Glass System

Richard Kerner’s Path Integral Approach Aims to Understand the Self-Organized Matter Agglomeration and Its Translation into the Energy Landscape Kinetics Paradigm

The glass transition as a boundary layer problem of the energy landscape kinetic master equations and its relationship with quantum path integrals

Contact Info

Product

Resources

About

Unusual Role of P–P Bonds on Melt Dynamics and Topological Phases of the Equimolar Ge_xP_xSe_100–2x Glass System

Unusual Role of P–P Bonds on Melt Dynamics and Topological Phases of the Equimolar Ge_xP_xSe_100–2x Glass System