Spinels manganate

Manganates III), again mixed-metal oxides present in the spinel Mn304, Mn Mn 204. 

Finally, NMR has also be used to study other spinels materials that do not contain manganese. For example, the intercalation/deintercalation of lithium titanate spinels such as Li4/3+Ji5/304 and Lii.i-Tii.904+a have been investigated. These materials may be used as anode materials in combination with cathodes operating at 4 V (vs Li) to produce cells with potentials of ca. 2.5 V. These materials are either diamagnetic or metallic, and unlike the mangan-ates, only very small differences in shifts are seen for Li in the different sites of the spinel structure. Nonetheless, these shift differences are enough to allow the concentrations of the different sites to be quantified and monitored following insertion of Li or as a function sample preparation method. ... 

Between 130 and 200 "C reversible disproportionation of Mn is observed in both NaOH and Transition-metal manganates of the spinel structure... 

In addition to the above reported synthesis of ferrites our search has revealed that aluminates [119], nickelates [120], and manganates [121], have also been prepared by the sonochemical method. Nanosized nickel aluminate spinel particles have been synthesized [119] with the aid of ultrasound radiation by a precursor approach. Sonicating an aqueous solution of nickel nitrate, aluminum nitrate, and urea yields a precursor which, on heating at 950 °C for 14 h yields nanosized N1A1204 particles with a size of ca. 13 nm and with a surface area of about 108 m g-i. 

Kim K. J., Lee J. H. Effects of nickel doping on structural and optical properties of spinel lithium manganate thin films. Solid State Commun. 2007,141,99-103. 

---