Robust Crystal Phase Separation with Distinct Charge, Orbital, and Spin Orders in AgMn7O12.
Inorg Chem
; 63(6): 3191-3198, 2024 Feb 12.
Article
in En
| MEDLINE
| ID: mdl-38294201
ABSTRACT
An AA'3B4O12-type A-site-ordered quadruple perovskite oxide AgMn7O12 was prepared by high-pressure and high-temperature methods. At room temperature, the compound crystallizes into a cubic Im3Ì
symmetry with a charge distribution of AgMn33+Mn43.5+O12. With the temperature decreasing to TCO,OO ≈ 180 K, the compound undergoes a structural phase transition toward a monoclinic C2/m symmetry, giving rise to a B-site charge- and orbital-ordered AgMn33+Mn23+Mn24+O12 phase. Moreover, this charge-/orbital-ordered main phase coexists with the initial cubic AgMn33+Mn43.5+O12 phase in the wide temperature range we measured. The charge-/orbital-ordered phase shows two antiferromagnetic phase transitions near 125 and 90 K, respectively. Short-range ferromagnetic correlations are found to occur for the initial B-site mixed cubic phase around 35 K. Because of the robust phase separation, considerable magnetoresistance effects are observed below TCO,OO in AgMn7O12.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Inorg Chem
Year:
2024
Document type:
Article
Affiliation country:
China