Configurational Entropy Relaxation of Silica Glass-Molecular Dynamics Simulations.

Entropy (Basel)

Department of Glass and Ceramics, University of Chemistry and Technology Prague, Technicka 5, CZ-166 28 Prague, Czech Republic.

Published: July 2021

Vitreous silica was modelled using molecular dynamics (MD). The glass structure was transferred into an undirected graph and decomposed into disjoint structural units that were ideally mixed to calculate the configurational entropy. The Debye relaxation model was suggested to simulate the evolution of entropy during the cooling of the system. It was found that the relaxation of the configurational entropy of MD corresponds to the effective cooling rate of 6.3 × 10 Ks and its extrapolation to 0.33 Ks mimics the glass transition with ; close to the experimental value. Debye relaxation correctly describes the observed MD evolution of configurational entropy and explains the existence of freezing-in temperature and the shape of the curve in the transition region.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8305701PMC
http://dx.doi.org/10.3390/e23070885DOI Listing

Publication Analysis

Top Keywords

configurational entropy
16
debye relaxation
8
configurational
4
relaxation
4
entropy relaxation
4
relaxation silica
4
silica glass-molecular
4
glass-molecular dynamics
4
dynamics simulations
4
simulations vitreous
4

Similar Publications

Entropy engineering activation of UiO-66 for boosting catalytic transfer hydrogenation.

Nat Commun

January 2025

State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, 130012, Changchun, P. R. China.

High-entropy metal-organic frameworks (HE-MOFs) hold promise as versatile materials, yet current rare examples are confined to low-valence elements in the fourth period, constraining their design and optimization for diverse applications. Here, a novel high-entropy, defect-rich and small-sized (32 nm) UiO-66 (ZrHfCeSnTi HE-UiO-66) has been synthesized for the first time, leveraging increased configurational entropy to achieve high tolerance to doping with diverse metal ions. The lattice distortion of HE-UiO-66 induces high exposure of metal nodes to create coordination unsaturated metal sites with a concentration of 322.

View Article and Find Full Text PDF

The backbone extraction process is pivotal in expediting analysis and enhancing visualization in network applications. This study systematically compares seven influential statistical hypothesis-testing backbone edge filtering methods (Disparity Filter (DF), Polya Urn Filter (PF), Marginal Likelihood Filter (MLF), Noise Corrected (NC), Enhanced Configuration Model Filter (ECM), Global Statistical Significance Filter (GloSS), and Locally Adaptive Network Sparsification Filter (LANS)) across diverse networks. A similarity analysis reveals that backbones extracted with the ECM and DF filters exhibit minimal overlap with backbones derived from their alternatives.

View Article and Find Full Text PDF

Multi-state metastability in neuroimaging signals reflects the brain's flexibility to transition between network configurations in response to changing environments or tasks. We modeled these dynamics with a Kuramoto network of 90 nodes oscillating at an intrinsic frequency of 40 Hz, interconnected using human brain structural connectivity strengths and delays. We simulated this model for 30 min to generate multi-state metastability.

View Article and Find Full Text PDF

Designing mimosine-containing peptides as efficient metal chelators: Insights from molecular dynamics and quantum calculations.

J Inorg Biochem

December 2024

Faculty of Chemistry (UPV/EHU), Manuel Lardizabal 3, Donostia-San Sebastian 20018, Spain; DIPC, Manuel Lardizabal 4, Donostia-San Sebastian 20018, Spain. Electronic address:

Mimosine, a non-essential amino acid derived from plants, has a strong affinity for binding divalent and trivalent metal cations, including Zn, Ni, Fe, and Al. This ability endows mimosine with significant antimicrobial and anti-cancer properties, making it a promising candidate for therapeutic applications. Previous research has demonstrated the effectiveness of mimosine-containing peptides as metal chelators, offering a safer alternative to conventional chelation agents.

View Article and Find Full Text PDF

Transition metal carbides, nitrides, and carbonitrides (MXenes) have emerged as a promising class of 2D materials that can be used for various applications. Recently, a new form of high-entropy MXenes has been reported, which contains an increased number of elemental species that can increase the configurational entropy and reduce the Gibbs free energy. The unique structure and composition lead to a range of intriguing and tunable characteristics.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!