Anomalous diffusion of water molecules at grain boundaries in ice Ih

2018 ◽  
Vol 20 (20) ◽  
pp. 13944-13951 ◽  
Author(s):  
Pedro Augusto Franco Pinheiro Moreira ◽  
Roberto Gomes de Aguiar Veiga ◽  
Ingrid de Almeida Ribeiro ◽  
Rodrigo Freitas ◽  
Julian Helfferich ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulations ◽  
Grain Boundaries ◽  
Anomalous Diffusion ◽  
First Principles ◽  
Water Molecules ◽  
Diffusive Behavior ◽  
Classical Molecular Dynamics ◽  
Dynamics Simulations

First-principles and classical molecular dynamics simulations show that diffusion of water molecules at pre-melted grain boundaries in ice is glassy-like, showing sub-diffusive behavior.

On the structure of biomedical silver-doped phosphate-based glasses from molecular dynamics simulations

2014 ◽  
Vol 16 (39) ◽  
pp. 21135-21143 ◽  
Author(s):  
Richard I. Ainsworth ◽  
Jamieson K. Christie ◽  
Nora H. de Leeuw
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulations ◽  
First Principles ◽  
Classical Molecular Dynamics ◽  
Dynamics Simulations

First-principles and classical molecular dynamics simulations have been carried out on undoped and silver-doped phosphate-based glasses with 50 mol% P2O5, 0–20 mol% Ag2O, and varying amounts of Na2O and CaO.

Insights into structural and dynamical features of water at halloysite interfaces probed by DFT and classical molecular dynamics simulations

2016 ◽  
Vol 18 (3) ◽  
pp. 2164-2174 ◽  
Author(s):  
Davide Presti ◽  
Alfonso Pedone ◽  
Giordano Mancini ◽  
Celia Duce ◽  
Maria Rosaria Tiné ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulations ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Water Molecules ◽  
Functional Theory ◽  
Structure And Dynamics ◽  
Classical Molecular Dynamics ◽  
Dynamical Features ◽  
Dynamics Simulations

Density functional theory calculations and classical molecular dynamics simulations have been used to investigate the structure and dynamics of water molecules on kaolinite surfaces and confined in the interlayer of a halloysite model of nanometric dimension.

First principles and classical molecular dynamics simulations of solvated benzene

2008 ◽  
Vol 128 (1) ◽  
pp. 014501 ◽  
Author(s):  
Markus Allesch ◽  
Felice C. Lightstone ◽  
Eric Schwegler ◽  
Giulia Galli
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulations ◽  
First Principles ◽  
Classical Molecular Dynamics ◽  
Dynamics Simulations

Model atomistic protrusions favouring the ordering and retention of water

2014 ◽  
Vol 16 (30) ◽  
pp. 15856-15865
Author(s):  
Prithvi Raj Pandey ◽  
Sudip Roy
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulations ◽  
Water Molecules ◽  
Classical Molecular Dynamics ◽  
Dynamics Simulations

The ordering of water molecules near model linear atomistic protrusions is studied using classical molecular dynamics simulations.

scholarly journals Sub-diffusion and population dynamics of water confined in soft environments

Nanoscale ◽  
2016 ◽  
Vol 8 (6) ◽  
pp. 3314-3325 ◽  
Author(s):  
Samuel Hanot ◽  
Sandrine Lyonnard ◽  
Stefano Mossa
Keyword(s):  
Molecular Dynamics ◽  
Population Dynamics ◽  
Molecular Dynamics Simulations ◽  
Ionic Surfactants ◽  
Water Molecules ◽  
Matrix Interface ◽  
Diffusive Behavior ◽  
Water Matrix ◽  
Depth Analysis ◽  
Dynamics Simulations

By molecular dynamics simulations, we show that dynamics of water confined in ionic surfactants soft confining matrices is sub-diffusive. Our in-depth analysis reveals that this sub-diffusive behavior originates at the water–matrix interface, where water molecules can be trapped for extended periods of time.

scholarly journals Electrical Breakdown Mechanism of Transformer Oil with Water Impurity: Molecular Dynamics Simulations and First-Principles Calculations

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 123
Author(s):  
Bin Cao ◽  
Ji-Wei Dong ◽  
Ming-He Chi
Keyword(s):  
Molecular Dynamics ◽  
Thermal Diffusion ◽  
First Principles ◽  
Electrical Breakdown ◽  
Transformer Oil ◽  
Water Molecules ◽  
Conducting Channel ◽  
Breakdown Mechanism ◽  
Water Impurity ◽  
Dynamics Simulations

Water impurity is the essential factor of reducing the insulation performance of transformer oil, which directly determines the operating safety and life of a transformer. Molecular dynamics simulations and first-principles electronic-structure calculations are employed to study the diffusion behavior of water molecules and the electrical breakdown mechanism of transformer oil containing water impurities. The molecular dynamics of an oil-water micro-system model demonstrates that the increase of aging acid concentration will exponentially expedite thermal diffusion of water molecules. Density of states (DOS) for a local region model of transformer oil containing water molecules indicates that water molecules can introduce unoccupied localized electron-states with energy levels close to the conduction band minimum of transformer oil, which makes water molecules capable of capturing electrons and transforming them into water ions during thermal diffusion. Subsequently, under a high electric field, water ions collide and impact on oil molecules to break the molecular chain of transformer oil, engendering carbonized components that introduce a conduction electronic-band in the band-gap of oil molecules as a manifestation of forming a conductive region in transformer oil. The conduction channel composed of carbonized components will be eventually formed, connecting two electrodes, with the carbonized components developing rapidly under the impact of water ions, based on which a large number of electron carriers will be produced similar to “avalanche” discharge, leading to an electrical breakdown of transformer oil insulation. The water impurity in oil, as the key factor for forming the carbonized conducting channel, initiates the electric breakdown process of transformer oil, which is dominated by thermal diffusion of water molecules. The increase of aging acid concentration will significantly promote the thermal diffusion of water impurities and the formation of an initial conducting channel, accounting for the degradation in dielectric strength of insulating oil containing water impurities after long-term operation of the transformer.

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