The manganite Nd0.5Sr0.5MnO3: A rare distortion of the perovskite

The charge-ordered properties, characterized by a transition from an antiferromagnetic insulating to a ferromagnetic metallic state as temperature increases, have been evidenced for Nd0.5Sr0.5MnO3 with a transition temperature of 160K. The neutron diffraction and HREM study of this manganite at room temperature shows that the space group of this orthorhombic structure (a=5.43 Angstrom,b=7.63 Angstrom, c=5.48 Angstrom) is Imma. This new distortion of the perovskite structure is described and compared to that of the manganites with GdFeO3 type structure. The quasi absence of Jahn Teller distortion of manganese in this phase is ascribed to its metallic properties at room temperature. Copyright (C) 1996 Elsevier Science Lid