相关论文: Contributions to the mixed-alkali effect in molecu…

The mixed alkali or mixed mobile ion effect in glasses manifests itself by strong nonlinear variations of ionic transport properties upon mixing of different types of mobile ions. We develop a theory for this effect based on thermally…

We explore progress in understanding the behaviour of cation conducting glasses, within the context of an evolving ''dynamic structure model'' (DSM). This behaviour includes: in single cation glasses a strong dependence of ion mobility on…

Although molecular dynamics (MD) simulations are commonly used to predict the structure and properties of glasses, they are intrinsically limited to short time scales, necessitating the use of fast cooling rates. It is therefore challenging…

We present results of molecular dynamics simulations on lithium metasilicate over a broad range of temperatures for which the silicate network is frozen in but the lithium ions can still be equilibrated. The lithium dynamics is studied via…

Based on a hopping model we show how the mixed alkali effect in glasses can be understood if only a small fraction c_V ofthe available sites for the mobile ions is vacant. In particular, we reproduce the peculiar behavior of the internal…

Peculiarities of mixed cation effect in ternary glasses whose composition involves alkali and non-alkali unicharged ions and/or alkaline earth ions are explored within context of defect model for mixed mobile ion effect (V. Belostotsky, J.…

We report extensive molecular-dynamics simulation results for binary mixtures of hard spheres for different size disparities and different mixing percentages,for packing fractions up to 0.605 and over a characteristic time interval spanning…

The available sites for ions in a typical disordered ionic conductor are determined. For this purpose we devised a straightforward algorithm which via cluster analysis identifies these sites from long time ionic trajectories below the glass…

Applying coherent X-rays by the method of atomic-scale X-ray Photon Correlation Spectroscopy results in beam-induced dynamics in a number of oxide glasses. Here these studies are extended to rubidium and caesium borates with varying alkali…

Performing molecular dynamics simulations, we investigate the enormous slowdowns of water dynamics when approaching a glass transition or a solid interface. We show that both effects can be described on common grounds within a theoretical…

The dynamic slowdown in glass-forming liquids remains a central topic in condensed matter science. Here, we report a theoretical investigation of the microscopic origin of the slowdown in amorphous silica, a prototypical strong glass former…

We present the results of a molecular dynamics computer simulation in which we investigate the dynamics of silica. By considering different system sizes, we show that in simulations of the dynamics of this strong glass former surprisingly…

The progress in understanding the behavior of glassy mixed ionic conductors within the concept of the defect model for the mixed mobile ion effect (V. Belostotsky, J. Non-Cryst. Solids 353 (2007) 1078) is reported. It is shown that in a…

Molecular dynamics simulations are performed to study the lithium jumps in LiPO3 glass. In particular, we calculate higher-order correlation functions that probe the positions of single lithium ions at several times. Three-time correlation…

Using molecular dynamics simulations we investigate the finite-size dependence of the dynamical properties of a diatomic supercooled liquid. The simplicity of the molecule permits us to access the microsecond time scale. We find that the…

Using large-scale molecular dynamics simulations, we investigate the surface properties of lithium, sodium, and potassium silicate glasses containing 25 mole % of alkali oxide. The comparison of two types of surfaces, a melt-formed surface…

We investigate how structural relaxation in mixtures with strong dynamical asymmetry is affected by the microscopic dynamics. Brownian and Newtonian dynamics simulations of dense mixtures of fast and slow hard spheres reveal a striking…

With molecular dynamics simulations of a fluid mixture of classical particles interacting with pair-wise additive Weeks-Chandler-Andersen potentials, we consider the time series of particle displacements and thereby determine distributions…

Glass-like materials are nonequilibrium systems where the relaxation time may exceed reasonable time scales of observations. In the present paper a dynamic percolation model is introduced in order to explain the principal properties of…

Structure and properties of magnesium silicate and borate melts and glasses were investigated by using newly parameterized interaction potentials in molecular dynamics simulations and compared with those of calcium silicate and borate. The…