TY - JOUR
T1 - Pressure-induced charge-transfer and structural transition in hexagonal multiferroic HoMnO3
AU - Ottesen, Martin
AU - Ehrenreich-Petersen, Emma
AU - Kronbo, Camilla Hjort
AU - Baudelet, François
AU - Nataf, Lucie
AU - Kantor, Innokenty
AU - Jørgensen, Mads Ry Vogel
AU - Bremholm, Martin
N1 - Publisher Copyright:
© 2023 American Physical Society.
PY - 2023/4
Y1 - 2023/4
N2 - The structural properties of the hexagonal multiferroic h-HoMnO3 under high pressure have been explored using synchrotron x-ray diffraction and x-ray absorption spectroscopy in diamond anvil cells. The structure was found to undergo a pressure-induced phase transition at ∼24 GPa to a rhombohedrally distorted superstructure, which is isostructural to the oxygen-loaded h-RMnO3+δ (R=Y,Dy,Ho,Er; δ≈0.28) phases found in the same systems. The driving force behind the phase transition is the highly compressible ab plane which facilitates a gradual charge disproportionation of Mn(III) with pressure. We speculate this stabilizes the spin-liquid phase due to ferromagnetic coupling between neighboring Mn(II)/Mn(IV) and Mn(III). In addition, we demonstrate that the structural behavior is highly susceptible to nonhydrostatic conditions and the choice of pressure medium should be carefully made.
AB - The structural properties of the hexagonal multiferroic h-HoMnO3 under high pressure have been explored using synchrotron x-ray diffraction and x-ray absorption spectroscopy in diamond anvil cells. The structure was found to undergo a pressure-induced phase transition at ∼24 GPa to a rhombohedrally distorted superstructure, which is isostructural to the oxygen-loaded h-RMnO3+δ (R=Y,Dy,Ho,Er; δ≈0.28) phases found in the same systems. The driving force behind the phase transition is the highly compressible ab plane which facilitates a gradual charge disproportionation of Mn(III) with pressure. We speculate this stabilizes the spin-liquid phase due to ferromagnetic coupling between neighboring Mn(II)/Mn(IV) and Mn(III). In addition, we demonstrate that the structural behavior is highly susceptible to nonhydrostatic conditions and the choice of pressure medium should be carefully made.
UR - http://www.scopus.com/inward/record.url?scp=85158843399&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.107.134115
DO - 10.1103/PhysRevB.107.134115
M3 - Journal article
AN - SCOPUS:85158843399
SN - 2469-9950
VL - 107
JO - Physical Review B
JF - Physical Review B
IS - 13
M1 - 134115
ER -