Bjerrum length

The Bjerrum length (after Danish chemist Niels Bjerrum 1879–1958 ) is the separation at which the electrostatic interaction between two elementary charges is comparable in magnitude to the thermal energy scale, ${\displaystyle k_{B}T}$, where ${\displaystyle k_{B}}$ is the Boltzmann constant and ${\displaystyle T}$ is the absolute temperature in Kelvin. This length scale arises naturally in discussions of electrostatic, electrodynamic and electrokinetic phenomena in electrolytes, polyelectrolytes and colloidal dispersions.

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