Effect of hole doping on the magnetic properties of the Mott-Hubbard antiferromagnetic insulator Nd1−xTiO3

The magnetic properties of the hole(x) doped Mott-Hubbard, antiferromagnetic insulator, NdTiO3, have been investigated in Nd1−xTiO3. For the materials in 0.010(6)≤x≤0.112(4), a correlation between the structural and magnetic properties is discussed with respect to the Ti-O-Ti angles and the Ti-O bond distances. For 0.010(6)≤x≤0.071(10), long-range magnetic order is observed through low-temperature neutron diffraction and heat capacity. Néel ordering temperatures of 88.2 and 61.9K are determined, respectively, for x=0.019(6) and x=0.064(10). From high-resolution neutron diffraction, the Pnma magnetic structure is assigned, unambiguously, as GxCy on Ti3+ and Cy2 on Nd3+. The Ti3+ ordered moment decreases gradually from 0.45(8)μB for x=0.019(6) to 0.31(7)μB for x=0.071(10), but vanishes abruptly for higher x. Antiferromagnetic short-range order exists for 0.074(9)≤x<0.098(10) as determined by neutron diffraction and the field dependence of the susceptibility. For 29(4)% hole doping in Nd1−xTiO3, x≥0.098(10), all magnetic ordering is destroyed.