6533b852fe1ef96bd12aad4a
RESEARCH PRODUCT
The dynamics of sodium in sodium disilicate: Channel relaxation and sodium diffusion
Kurt BinderJürgen HorbachWalter Kobsubject
PhysicsStatistical Mechanics (cond-mat.stat-mech)DiffusionSodiumRelaxation (NMR)Incoherent scatterFOS: Physical sciencesGeneral Physics and Astronomychemistry.chemical_elementAmorphous solidMatrix (mathematics)Nuclear magnetic resonancechemistryExponentAtomic physicsStructure factorCondensed Matter - Statistical Mechanicsdescription
We use molecular dynamics computer simulations to study the dynamics of amorphous (Na_2O)2(SiO_2). We find that the Na ions move in channels embedded in a SiO_2 matrix. The characteristic distance between these channels gives rise to a prepeak in the structure factor at around q=0.95 A^-1. The dynamics of sodium is given by a fast process which can be seen in the incoherent scattering function and a slow process which is seen in the coherent function. The relaxation time of the latter coincides with the alpha-relaxation time of the matrix. The Kohlrausch exponent of the fast process for q>1.6 A^1 is the same as the von Schweidler exponent for the slow one, demonstrating that the two processes are closely related.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2001-10-16 |