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Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
(FeO3)8O2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional and consists of two water molecules and one FeO3 framework. In the FeO3 framework, there are two inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 53–58°. There are a spread of Fe–O bond distances ranging from 1.82–2.21 Å. In the second Fe site, Fe is bonded to six O atoms to form corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 53–58°. There are a spread of Fe–O bond distances ranging from 1.82–2.26 Å. There are four inequivalent O sites. In the first O site, O is bonded in a trigonal planar geometry to two Fe and one O atom. The O–O bond length is 1.37 Å. In the second O site, O is bonded in a bent 120 degrees geometry to two Fe atoms. In the third O site, O is bonded in a trigonal planar geometry to two equivalent Fe and one O atom. The O–O bond length is 1.39 Å. In the fourth O site, O is bonded in a trigonal planar geometry to two equivalent Fe and one O atom.
(FeO3)8O2 is Upper Bainite-like structured and crystallizes in the orthorhombic Immm space group. The structure is three-dimensional and consists of two water molecules and one FeO3 framework. In the FeO3 framework, Fe is bonded to six O atoms to form corner-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 51–60°. There are a spread of Fe–O bond distances ranging from 1.92–2.03 Å. There are three inequivalent O sites. In the first O site, O is bonded in a distorted bent 120 degrees geometry to two equivalent Fe atoms. In the second O site, O is bonded in a bent 120 degrees geometry to two equivalent Fe atoms. In the third O site, O is bonded in a bent 120 degrees geometry to two equivalent Fe atoms.
FeO3SO3 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four sulfur trioxide molecules and four FeO3 clusters. In each FeO3 cluster, Fe is bonded in a distorted trigonal non-coplanar geometry to three O atoms. All Fe–O bond lengths are 1.62 Å. There are three inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Fe atom. In the second O site, O is bonded in a single-bond geometry to one Fe atom. In the third O site, O is bonded in a single-bond geometry to one Fe atom.
Multiferroics that combine ferroelectricity and magnetic order are attractive for electronic and spintronic technologies, yet chemical disorder that promotes relaxor ferroelectricity usually suppresses long-range magnetic order. Here, we report entropy-stabilized relaxor multiferroicity in epitaxial hexagonal (Tb0.2Dy0.2Ho0.2Lu0.2Yb0.2)FeO3 thin films. Structural, magnetic, dielectric, and synchrotron spectroscopic measurements show the coexistence of relaxor ferroelectricity and long-range ferromagnetic order. We find that improper ferroelectricity remains robust against A-site configurational disorder, while the Fe sublattice preserves magnetic exchange. This separation of the microscopic origins of the polar and magnetic responses enables chemically disordered multiferroicity. Our results establish entropy engineering in hexagonal ferrites as a route toward multifunctional oxide thin films and provide a general design strategy for high-entropy multiferroics.