Lanthanum manganite

Lanthanum manganite, LaMnO₃, is a mixed oxide of lanthanum and manganese(III). It adopts the perovskite structure.

Lanthanum manganite is usually encountered doped with monovalent or (especially) divalent metal ions such as strontium, to give a compound of formula La_1−xM_xMnO₃, where x is typically 0.1–0.2. This forces an equivalent proportion of the manganese ions (double the portion if M is monovalent) to be oxidized from manganese(III) to manganese(IV). These doped lanthanum manganites show colossal magnetoresistance (CMR).