Curie constant

In magnetism, 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 in kelvins (K),[1] by

,[2]

where is the number of magnetic atoms (or molecules) per unit volume, is the Landé g-factor, is the Bohr magneton, is the angular momentum quantum number and is Boltzmann's constant. For a two-level system with magnetic moment , the formula reduces to

,

while the corresponding expressions in Gaussian units are

,
.

The constant is used in Curie's Law, which states that for a fixed value of an applied magnetic field , the magnetization of a material is (approximately) inversely proportional to temperature.

.

This equation was first derived by Pierre Curie.

Because of the relationship between magnetic susceptibility , magnetization and applied magnetic field is almost linear at low fields, then

,

this shows that for a paramagnetic system of non-interacting magnetic moments, magnetization is inversely related to temperature .

See also

References

  1. Coey, J. M. D.; Coey, J. M. D. (2010-03-25). Magnetism and Magnetic Materials. Cambridge University Press. ISBN 978-0-521-81614-4.
  2. Kittel, Charles (11 November 2004). Introduction to Solid State Physics, 8th Edition. Wiley. pp. 304. ISBN 0-471-41526-X.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.