The Mixed Akali Effect in Ternary Alkali Silicate Melts: Insight from Molecular Dynamics Computer simulations

  • H. Knoth
  • J. Horbach
  • K. Binder
Conference paper


Large scale molecular dynamics (MD) computer simulations are used to study the amorphous alkali silicates (Li2O)(2·SiO2) [LS2], (K2O)(2·SiO2) [KS2], and (0.5·Li2O)(0.5·K2O)(2·SiO2) [LKS2]. These systems are characterized by a fast alkali ion motion in a relatively immobile Si-0 matrix. We investigate the so-called mixed alkali effect (MAE) which is reflected as a significant decrease of the alkali ion diffusion constants in LKS2 as compared to the corresponding binary systems LS2 and KS2. We show that the subtle interplay between the structure on intermediate length scales and the alkali diffusion is important to understand the microscopic origin of the MAE.


Microscopic Origin Alkali Oxide Partial Structure Factor Alkali Silicate Mixed Alkali Effect 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • H. Knoth
    • 1
  • J. Horbach
    • 1
  • K. Binder
    • 1
  1. 1.Institut für PhysikJohannes Gutenberg-UniversitätMainzGermany

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