Specific heat of Cd-doped manganites

In the present work, the specific heat of La-0.5(Ca0.5-xCdx)MnO3 double doped manganites at the doping concentrations x = 0.0-0.5 are computed for the first time for understanding the thermodynamic behaviors in manganites using interatomic potential by Renu Choithrani et al. The crystal structure of given manganites with space group Prima have an orthorhombic structure except La0.5Cd0.5MnO3, which instead shows a rhombohedral (R3c) space group. These materials find extensive technological applications in magnetic sensors, computer hard drive reader, logic devices, etc. The interatomic potential has been applied to study the specific heat (C-p) as a function of temperature. The trends of variation of our computed specific heats with temperature are in agreement with corresponding experimental data by Wang et al. for almost all the compositions (x) of La-0.5(Ca0.5-xCdx)MnO3 with minor deviations at higher temperatures. The specific heats are found to increase with temperature from 2 to 300 K. The values of specific heats also increase with composition (x) when we go from x = 0.0 to 0.5 in these manganites. These features are exhibited by both the experimental and our theoretical results. In addition, we have used modified rigid ion model (MRIM) developed from the interatomic potential to compute the thermodynamical parameters whose results are discussed in detail for the present system of Cd-doped manganites. (C) 2010 Elsevier B.V. All rights reserved.