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Manganite (other)
Manganite a mineral composed of manganese oxide-hydroxide, MnO(OH). Manganite may also refer to: * Lanthanum manganite, an inorganic compound with the formula LaMnO3 * Lanthanum strontium manganite Lanthanum strontium manganite (LSM or LSMO) is an oxide ceramic material with the general formula La1−xSrxMnO3, where ''x'' describes the doping level. It has a perovskite-based crystal structure, which has the general form ABO3. In the crysta ..., an oxide ceramic material * Potassium manganite {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manganite
Manganite is a mineral composed of manganese oxide-hydroxide, MnO(OH), crystallizing in the monoclinic system (pseudo-orthorhombic). Crystals of manganite are prismatic and deeply striated parallel to their length; they are often grouped together in bundles. The color is dark steel-grey to iron-black, and the luster brilliant and submetallic. The streak is dark reddish brown. The hardness is 4, and the specific gravity is 4.3. There is a perfect cleavage parallel to the brachypinacoid, and less-perfect cleavage parallel to the prism faces. Twinned crystals are not infrequent. The mineral contains 89.7% manganese sesquioxide; it dissolves in hydrochloric acid with evolution of chlorine. Occurrence Manganite occurs with other manganese oxides in deposits formed by circulating meteoric water in the weathering environment in clay deposits and laterites. It forms by low temperature hydrothermal action in veins in association with calcite, barite, and siderite. Often associated w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lanthanum Manganite
Lanthanum manganite is an inorganic compound with the formula LaMnO3, often abbreviated as LMO. Lanthanum manganite is formed in the perovskite structure, consisting of oxygen octahedra with a central Mn atom. The cubic perovskite structure is distorted into an orthorhombic structure by a strong Jahn–Teller distortion of the oxygen octahedra. LaMnO3 often has lanthanum vacancies as evidenced by neutron scattering. For this reason, this material is usually referred as LaMnO3+ẟ. These vacancies generate a structure with a rhombohedral unit cell in this perovskite. A temperatures below 140 K, this LaMnO3+ẟ semiconductor exhibit a ferromagnetic order. Synthesis Lanthanum manganite can be prepared via solid-state reactions at high temperatures, using their oxides or carbonates. An alternative method is to use lanthanum nitrate and manganese nitrate as raw materials. The reaction occurs at high temperature after the solvents are vaporized. Lanthanum manganite alloys Lant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lanthanum Strontium Manganite
Lanthanum strontium manganite (LSM or LSMO) is an oxide ceramic material with the general formula La1−xSrxMnO3, where ''x'' describes the doping level. It has a perovskite-based crystal structure, which has the general form ABO3. In the crystal, the 'A' sites are occupied by lanthanum and strontium atoms, and the 'B' sites are occupied by the smaller manganese atoms. In other words, the material consists of lanthanum manganite with some of the lanthanum atoms substitutionally doped with strontium atoms. The strontium (valence 2+) doping on lanthanum (valence 3+) introduces extra holes in the valence band and thus increases electronic conductivity. Depending on the x value in La1−xSrxMnO3, the unit cell of LSMO can be rhombohedral, cubic, or hexagonal. This change in the unit cell is explained on the basis of the Goldschmidt tolerance factor for perovskites. The change in the oxidation state of the Mn cation in LSMO can be readily observed through the position of the XPS pea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
