Structural and magnetic properties of the (Ca1-xNax)(Fe2-xTix)O4 solid solution (0≤x≤1)

New compounds corresponding to the (Ca1-xNax)(Fe2-xTix)O-4 formula with 0 <= x <= 1 were prepared by solid state reactions at 1100 degrees C in air. A continuous solid solution was found between end members CaFe2O4 and NaFeTiO4. The evolution of structural parameters and bonding geometry with composition is discussed in detail. Magnetic measurements show that the antiferromagnetic ordering known in CaFe2O4 is suppressed for all x values investigated (x >= 0.2). The absence of crystallographic transition at low temperature was checked by X-ray diffraction down to 10 K. The magnetic structure of CaFe2O4 was redetermined from powder neutron diffraction. Spins on the two iron sites order antiparallel (FzFz spin arrangement), as described previously. The difference in magnetic moments on Fe, and Fe, sites result in a ferrimagnetic configuration with net moment 2.72 mu(B) at 2 K. (c) 2007 Elsevier B.V. All rights reserved.