Studies on the magnetic and structural phase transitions of Nd3RuO7

Crystal structures and magnetic and thermal properties of neodymium ruthenate Nd3RuO7 have been investigated. The specific heat and neutron diffraction measurements showed a monoclinic-orthorhombic structural phase transition at 130 K. The monoclinic crystal structure at 100 K is well described with the space group P2(1)/m (a = 10.8893(4) Angstrom, b = 7.3864(2) Angstrom, c = 7.4731(2) Angstrom and beta = 90.008(6)degrees). The results of the magnetic susceptibility measurements show the existence of the antiferromagnetic transition with a weak ferromagnetic component at 19K. Specific heat and neutron diffraction measurements also indicated long-range magnetic ordering of both Nd3+ and Ru5+ ions below 19 K. The magnetic sublattice of Nd3+, ions was twice as large as the size of the crystal lattice along the b-axis. On the other hand, the size of the magnetic sublattice of Ru5+ was the same as that of the crystal lattice. Ru5+ ions were coupled anti-ferromagnetically along the c-axis.