Curie–Weiss law
Quick Summary
The Curie-Weiss law describes the magnetic susceptibility of a paramagnetic substance. It states that susceptibility is inversely proportional to the temperature exceeding the Curie point, below which the substance is no longer paramagnetic.1
Magnetic susceptibility quantifies how easily a material can be magnetized. Materials are classified as diamagnetic, paramagnetic, or ferromagnetic based on this property. Paramagnetic materials, like platinum, slightly increase a magnetic field because their atomic magnetic dipole moments align with the external field. The Curie-Weiss law refines Curie's law, which states that susceptibility is inversely proportional to absolute temperature (\u03c7 = C/T). The modified equation is \u03c7 = C/(T - \u03b8), where \u03b8 is a constant. This indicates that at T = \u03b8, susceptibility becomes infinite, and the material transitions to a ferromagnetic state.23
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magnetismMagnetic properties of matterThis equation is called the Curie–Weiss law (after Curie and Pierre-Ernest Weiss, another French physicist). From the form of this last equation, it is clear that at the temperature T = θ, the value of the susceptibility becomes infinite. Below this temperature, the material exhibits spontaneous magnetization—i.e., it becomes ferromagnetic.…
Read MoreThis equation is called the Curie–Weiss law (after Curie and Pierre-Ernest Weiss, another French physicist). From the form of this last equation, it is clear that at the temperature T = θ, the value of the susceptibility becomes infinite. Below this temperature, the material exhibits spontaneous magnetization—i.e., it becomes ferromagnetic.…
Read More- magnetismRole of exchange interaction
This result, the Curie–Weiss law, is valid at temperatures greater than the Curie temperature Tc (see below); at such temperatures the substance is still paramagnetic because the magnetization is zero when the field is zero. The internal field, however, makes the susceptibility larger than that given by the…
Read MoreThis result, the Curie–Weiss law, is valid at temperatures greater than the Curie temperature Tc (see below); at such temperatures the substance is still paramagnetic because the magnetization is zero when the field is zero. The internal field, however, makes the susceptibility larger than that given by the…
Read More