Lanthanum manganite

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Lanthanum manganite
IUPAC name lanthanum oxide—manganese(III) oxide (1/1)
Identifiers
InChI InChI=1/La.Mn.3O/q2*+3;3*-2
Properties
Chemical formula LaMnO3
Molar mass 241.84 g mol−1
Structure
Crystal structure Perovskite
Coordination geometry Distorted octahedral (Mn3+)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)

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 La1−xMxMnO3, 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).[1][2][3] The strontium-doped material is a half-metal for x = 0.3.[4]

References

  1. McCormack, M.; Jin, S.; Tiefel, T. H.; Fleming, R. M.; Phillips, Julia M.; Ramesh, R. Very large magnetoresistance in perovskite-like La-Ca-Mn-O thin films. Appl. Phys. Lett. 1994, 64, 3045–47. DOI: 10.1063/1.111372.
  2. Gubkin, M. K.; Perekalina, T. M. Pis'ma Zh. Eksp. Teor. Fiz. 1994, 60 (10), 727–30; Nature of the giant magnetoresistance in ferromagnetic lanthanum manganates. JETP Lett. 1994, 60 (10), 747–50, <http://www.jetpletters.ac.ru/ps/1357/article_20515.pdf>.
  3. Ramirez, A. P. Colossal magnetoresistance. J. Phys.: Cond. Matter, 9 (39), 8171. DOI: 10.1088/0953-8984/9/39/005.
  4. Park, J.-H.; Vescovo, E.; Kim, H.-J.; Kwon, C.; Ramesh, R.; Venkatesan, T. Direct evidence for a half-metallic ferromagnet. Nature 1998, 392, 794–96. DOI: 10.1038/33883.
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