Effect of B-Site Order–Disorder in the Structure and Magnetism of the New Perovskite Family La 2 MnB′O 6 with B′ = Ti, Zr, and Hf

ARCINIEGAS JAIMES, DIANA M.; DE PAOLI, JUAN M.; NASSIF, VIVIAN; BERCOFF, PAULA G.; TIRAO, GERMÁN; CARBONIO, RAÚL E.; POMIRO, FERNANDO

INORGANIC CHEMISTRY

AMER CHEMICAL SOC

Lugar: Washington; Año: 2021 vol. 60 p. 4935 - 4944

0020-1669

Inthis work we report the synthesis as well as the structural and magneticcharacterisation of the three perovskites La2MnB?O6 (B?= Ti, Zr and Hf). Interestingly,only La2MnTiO6 crystallizes in the monoclinic doubleperovskite space group P21/n,with complete rocksalt order of the B-site cations, whereas La2MnZrO6and La2MnHfO6 crystallize in the orthorhombic simpleperovskite space group Pbnm, withcomplete disorder in the B-site. Moreover, the magnetic susceptibility at lowtemperatures shows clear antiferromagnetic transitions below 10 K for the threecompounds, but only the Ti-based perovskite has long-range magnetic ordering. Thelatter compound has an antiferromagnetic Type-II structure described by the PS-1magnetic space group while the other two have a spin-glass behaviour below thetransition temperature due to both spin disorder and competing superexchangeinteractions in the systems. This is the first timethat two of the three studied compounds were synthesized (B?= Zr and Hf) and thefirst time that the whole series is described in thorough detail usingsymmetry-adapted refinements and magnetic crystallography.