Hole doping into the metastable LuMnO3 perovskite

Single-phase samples of (Lu1−xCax)MnO3 of the orthorhombic perovskite structure have been realized through solid-state synthesis under high pressures for the Ca contents 0 ≤ x ≤ 0.3 and at ambient pressure for x = 0.5 . The samples were characterized for basic structural, magnetic and transport properties with respect to x . With increasing x , Mn is gradually oxidized and the cooperative Jahn–Teller distortion appears to diminish. Increasing the concentration of MnIV at the expense of MnIII was found to enhance the ferromagnetic-like interactions and decrease electrical resistivity. Efforts to dope the orthorhombic LuMnO3 perovskite phase with holes by other means than the aliovalent CaII-for- LuIII substitution turned out to be infeasible: the larger alkaline earth element, Sr, did not enter the phase and high-pressure oxygenation treatments resulted in stabilization of the Lu2Mn2O7 pyrochlore phase.