Colossal Magnetoresistance Manganite Perovskites:  Relations between Crystal Chemistry and Properties

Abstract

Manganites with the perovskite structure represent a very important family of oxides which are extensively studied for their colossal magnetoresistance (CMR) properties. In the present review we discuss the different factors which govern the magnetic and transport properties of these materials: carrier concentration, average size of the interpolated cation, and mismatch effect on the A-site. Three types of oxides are mainly examined: (i) the hole doped manganites Ln 0.7 A 0.3 MnO 3 (A = Ca, Sr, Ba), (ii) the “charge ordered” Ln 0.5 A 0.5 MnO 3 manganites, and (iii) the electron doped manganites Ca 1 - x Ln x MnO 3 and Ca 1 - x Th x MnO 3 . The relationships between structural and magnetic transitions are discussed, and particular attention is paid to charge ordering phenomena. The doping of the Mn sites by various elements (Al, Ga, In, Ti, Sn, Fe, Cr, Co, Ni) is systematically examined. The beneficial effect of “Cr, Co, Ni” elements, which induce CMR properties in these perovskites, is emphasized.