Hergemöller, Fabian; Wilangowski, Fabian: The interstitialcy diffusion mechanism in alkali feldspar : self-diffusion measurements and Monte Carlo simulations. 2017
Inhalt
- Introduction
- Fundamentals
- Alkali feldspar
- Diffusion in single-crystalline solids
- Fick's laws and solutions of the diffusion equation
- Diffusion in anisotropic media
- Basic atomic diffusion mechanisms and correlation effects
- Microscopic migration energy
- Diffusion in binary alloys
- Sodium self-diffusion in single-crystal alkali feldspar
- Potassium self-diffusion in a K-rich single-crystal alkali feldspar
- Ionic conductivity in single-crystal alkali feldspar
- Vacancy-related diffusion correlation effects
- Computational procedures
- Results and discussion
- Correlation factors in a simple cubic alloy
- Correlation factors on the alkali sublattice in feldspar
- Vacancy percolation behaviour
- Summary and conclusions
- Correlation effects of the interstitialcy mechanism – sc random alloy
- Theoretical background
- Random alloy model with interstitialcy diffusion
- Tracer diffusion coefficients
- Tracer correlation factors
- Interstitialcy diffusivity and related correlation factors
- Computational methods
- Results and Discussion
- Tracer correlation factors
- Interstitialcy correlation factors
- Percolation behaviour
- Comparison of tracer diffusion coefficients
- Comparison of mass and charge transport
- Summary and conclusions
- Effects of non-collinear and direct interstitial jumps
- Theoretical background
- Random alloy model with diffusion via self-interstitials
- Interstitialcy diffusion mechanism including non-collinear exchange
- Interstitialcy diffusion with allowance for direct interstitial jumps
- Numerical procedures
- Results and discussion
- Summary and conclusions
- Interstitialcy diffusion in alkali feldspar
- Theoretical background
- Random alloy model for diffusion via self-interstitials
- Interstitialcy diffusion in alkali feldspar along the b-axis
- Interstitialcy diffusion along the c∗-axis including double interstitialcy jumps
- Effective short-range interaction between cations
- Numerical procedures
- Results and discussion
- Percolation behaviour
- Dependence on effective short-range interactions between cations
- Dependence of jump frequencies from temperature
- Correlation effects below the percolation threshold
- Summary and conclusions
- Summary & Outlook
- 22Na tracer diffusion coefficients
- Bibliography