Pyroelectricity is the phenomenon that the charges appear on the surface of certain materials when they are heated or cooled. All pyroelectric materials have the character of piezoelectricity. Ferroelectric materials have pyroelectricity.

All crystal structures can be divided into 32 crystal classes (point groups). The 20 groups of these 32 point gourps,

    \[ 1, 2, m, mm2, 3, 3m, 4, 4mm, 6, 6mm \]

exhibit direct piezoelectricity.

Leave a Reply

Your email address will not be published. Required fields are marked *