Effect of cation doping on low-temperature specific heat of LaCoO3 cobaltate

Abstract We have computed the effect of strontium doping on the thermophysical properties of perovskite structure rare earth cobaltate, La 1− x Sr x CoO 3 (0.0≤ x ≤1.0) by means of a rigid ion model (RIM) in the temperature 0 K 2 ≤ T 2 ≤100 K 2 . The trends of variation of our computed specific heat with temperature are in agreement with corresponding experimental data. A meticulous attention was given to the investigation of the assumption that these cobaltate perovskites are Debye-like solids and obeys T 3 law at low temperature ( T θ D /50). Present investigations reaffirm the presence of strong electron–phonon interactions in these compounds. An interesting phenomenon was observed in C p / T vs. T 2 plot for x ≤0.2 below 15 K where linearity deviates, which suggests the gradual freezing of the entropy on cooling. In addition, the results on bulk modulus ( B ), cohesive energy ( ϕ ), molecular force constant ( f ), restsrahlen frequency ( υ ), and Debye temperature( θ D ) are also presented. The scope of further extension of the present model has also been discussed.