Effect of Oxygen Content on the Electrical Transport Properties of La0.4Ca0.6MnO3?y

The effect of oxygen content on the electrical transport properties of La 0.4 Ca 0.6 MnO 3-y was studied. Upon decreasing oxygen content, the lattice parameters a, b and c of the samples increase and the electrical resistivity of the samples also increases abruptly, contradicting what is expected in terms of Mn 4+ /Mn 3+ ratio. This work suggests that other factors rather than the ratio of Mn 4+ /Mn 3+ may play a role in determining the properties of La 0.4 Ca 0.6 MnO 3-y with less oxygen contents.