Paramagnetism

Paramagnetism is the tendency of the atomic magnetic dipoles, to align with an external magnetic field. This effect occurs due to quantum-mechanical spin as well as electron orbital angular momentum.

Curie's Law

Under relatively low magnetic field saturation when the majority of the atomic dipoles are not aligned with the field, paramagnetic materials exhibit magnetisation according to Curie's Law:

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mathbf{M} = C cdot rac{mathbf{B}}{T}

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where

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:M is the resulting magnetisation

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:B is the magnetic flux density of the applied field, measured in teslas

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:T is absolute temperature, measured in kelvins

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:C is a material-specific Curie constant

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This law indicates that paramagnetic materials tend to become increasingly magnetic as the applied magnetic field is increased, but less magnetic as temperature is increased. Curie's law is incomplete because it fails to predict the saturation that occurs when most of the atomic dipoles are aligned (after everything is aligned, increasing the external field will not increase the total magnetization). So the Curie constant, really should be expressed as a function of how much of the material is already aligned.

Related Topics:
Curie constant - Function

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