Transition temperature

Transition temperature is the temperature at which a material changes from one crystal state (allotrope) to another. For example, when rhombic sulfur is heated above 95.6°C it changes form into monoclinic sulfur. When cooled below 95.6°C it reverts to rhombic sulfur.

In the case of ferroelectric or ferromagnetic crystals a transition temperature may be known as the Curie temperature.

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