Structure and magnetism of the A site scandium perovskite (Sc 0.94 Mn 0.06 )Mn 0.65 Ni 0.35 O 3 synthesized at high pressure

Abstract

Scandium perovskite (Sc 0.94 Mn 0.06 )Mn 0.65 Ni 0.35 O 3 , synthesized at high pressure and high temperature, has a triclinic structure (space group ) at room temperature and ambient pressure with a √2 a p ×√2 a p ×2 a p structure with α ≈90 ° , β ≈89 ° , γ ≈90 ° . Magnetic measurements show that the material displays Curie–Weiss behaviour above 50 K with C =2.11 emu K mol −1 ( μ eff =4.11 μ B per formula unit) and θ =−95.27 K. Bond valence sum analysis of the crystal structure shows that manganese is present in three different oxidation states (+2, +3, +4), with the +2 oxidation state on the A site resulting in a highly tilted perovskite structure (average tilt 21.2 ° compared with 15.7 ° calculated for LaCaMnNbO 6 ), giving the formula .