title: Breaking the geometric magnetic frustration in controlled off-stoichiometric LuMn1+zO3+δ compounds.
abstract: This study explores controlled off-stoichiometric LuMn1+zO3+δ (|z| < 0.1) compounds, intended to retain the utter LuMnO3 intrinsic hexagonal symmetry and ferroelectric properties. X-ray powder diffraction measurements evidenced a single phase P63cm structure. Thermo-gravimetric experiments show a narrow impact of oxygen vacancies while a distinguishable gas exchange at ∼700 K, a surprisingly lower temperature when compared to perovskite systems. A comparison of different nominal ceramics revealed pertinent structural and magnetic property variations owing to subtle self-doping effects. Deviations from the archetypal antiferromagnetic state were detected below ∼90 K suggesting local rearrangements of the nominal Mn(3+) ions matrix, breaking the ideal geometrical spin frustration, leading to a non-compensated magnetic structure.
authors.affiliation: Physics Department & CICECO-AIM, Aveiro University, 3810-193 Aveiro, Portugal. ffigueiras@ua.pt and IFIMUP and IN-Institute of Nanoscience and Nanotechnology, Physics and Astronomy Department, Faculty of Sciences of University of Porto, 4169-007 Porto, Portugal.
authors.forename: F G
authors.initials: FG
authors.lastname: Figueiras
authors.affiliation: Physics Department & CICECO-AIM, Aveiro University, 3810-193 Aveiro, Portugal. ffigueiras@ua.pt.
authors.forename: D
authors.initials: D
authors.lastname: Karpinsky
authors.affiliation: Centro de Química, Trás-os-Montes & Alto-Douro University, 5001-801 Vila Real, Portugal.
authors.forename: P B
authors.initials: PB
authors.lastname: Tavares
authors.affiliation: Physics Department & CICECO-AIM, Aveiro University, 3810-193 Aveiro, Portugal. ffigueiras@ua.pt.
authors.forename: Soma
authors.initials: S
authors.lastname: Das
authors.affiliation: FAME, Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, 2629 JB Delft, Netherlands.
authors.forename: J V
authors.initials: JV
authors.lastname: Leitão
authors.affiliation: FAME, Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, 2629 JB Delft, Netherlands.
authors.forename: E H
authors.initials: EH
authors.lastname: Brück
authors.affiliation: IFIMUP and IN-Institute of Nanoscience and Nanotechnology, Physics and Astronomy Department, Faculty of Sciences of University of Porto, 4169-007 Porto, Portugal.
authors.forename: J Agostinho
authors.initials: JA
authors.lastname: Moreira
authors.affiliation: Physics Department & CICECO-AIM, Aveiro University, 3810-193 Aveiro, Portugal. ffigueiras@ua.pt.
authors.forename: V S
authors.initials: VS
authors.lastname: Amaral