Heat capacities of RCoO3(s) (R = La, Nd, Sm Eu, Gd, Tb, Dy and Ho) by differential scanning calorimetry

Ternary oxides, RCoO3(s) (R = La, Nd, Sm Eu, Gd, Tb, Dy and Ho), have been prepared by citrate–nitrate gel combustion route and characterized by X-ray diffraction analysis. Heat capacities of these compounds have been measured in the temperature range from 130 to 850 K using a heat flux type differential scanning calorimeter. Heat capacity versus temperature plots for these compounds indicated broad humps in the temperature range from 450 to 780 K suggesting electronic transitions in these compounds accompanied by large entropy increments. The transition temperatures showed increasing trend with decrease in ionic radii of the lanthanide ion.