Curie constant

The Curie constant is a material-dependent property that relates a material's magnetic susceptibility to its temperature.

The Curie constant, when expressed in SI units, is given by

where ${\displaystyle N}$ is the number of magnetic atoms (or molecules) per unit volume, ${\displaystyle g}$ is the Landé g-factor, ${\displaystyle \mu _{B}}$ (9.27400915e-24 J/T or A·m²) is the Bohr magneton, ${\displaystyle J}$ is the angular momentum quantum number and ${\displaystyle k_{B}}$ is Boltzmann's constant. For a two-level system with magnetic moment ${\displaystyle \mu }$, the formula reduces to

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