Physics:Self-diffusion
According to IUPAC definition,[1] self-diffusion coefficient is the diffusion coefficient [math]\displaystyle{ D_i^* }[/math] of species [math]\displaystyle{ i }[/math] when the chemical potential gradient equals zero. It is linked to the diffusion coefficient [math]\displaystyle{ D_i }[/math] by the equation: [math]\displaystyle{ D_i^*=D_i\frac{\partial\ln c_i}{\partial\ln a_i}. }[/math]
Here, [math]\displaystyle{ a_i }[/math] is the activity of the species [math]\displaystyle{ i }[/math] in the solution and [math]\displaystyle{ c_i }[/math] is the concentration of [math]\displaystyle{ i }[/math]. This term is commonly assumed to be equal to the tracer diffusion determined by watching the movement of an isotope in the material of interest.
See also
References
- ↑ S. J. Chalk (1997). "IUPAC Compendium of Chemical Terminology 'The Gold Book'". in A. D. McNaught, A. Wilkinson. Blackwell Scientific Publications. https://goldbook.iupac.org/terms/view/S05582.
![]() | Original source: https://en.wikipedia.org/wiki/Self-diffusion.
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