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mp-19306: Fe3O4 (cubic, Fd-3m, 227)

Fe3O4 is Spinel-derived structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are three inequivalent Fe+2.67+ sites. In the first Fe+2.67+ site, Fe+2.67+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six equivalent FeO4 tetrahedra and edges with six FeO6 octahedra.

Magnetite - Sandatlas

Magnetite (Fe 3 O 4) is a common iron oxide mineral.It is a member of the spinel group. These are minerals that share the same structure but differ in chemical composition. Other notable members of the group are chromite and spinel.Magnetite is among the two major sources of iron.

Structure and Formation of the Magnetite-Bearing Cap of ...

Abstract. Scanning electron microscopy was employed to study the ultrastructure of the magnetite-bearing cap in mature tricuspid teeth of four chiton species: Lepidochitona cinerea, Mopalia muscosa, Katharina tunicata, and Cryptochiton stelleri.The cap is composed of parallel rod-shaped units.

Structure, morphology and crystal growth of anisotropic ...

Bacterial magnetite particles of anisotropic morphology have been studied by high-resolution transmission electron microscopy. Lattice images of individual crystals are consistent with a well-ordered magnetite cubic inverse spinel structure.

Magnetite | Fe3O4 - PubChem

Magnetite | Fe3O4 or Fe3H2O4 | CID 14789 - structure, chemical names, physical and chemical properties, classification, patents, literature, biological activities ...

A density functional theory investigation of the ...

8/5/2014· Magnetite has a cubic inverse spinel structure (space group ) at room temperature with 8 formula units (f.u.) in the conventional unit cell as shown in figure 1. Its chemical formula, often written as [Fe 3+ ] A [Fe 3+,Fe 2+ ] B O 4, indicates that the tetrahedral sites denoted as A are occupied by ferric ions while octahedral sites denoted ...

Uniform spheroidal nanoassemblies of magnetite using Tween ...

We report solvothermal synthesis of uniform spheroidal nanoassemblies of magnetite (Fe3O4) in ethylene glycol medium by using polyethoxylated surfactants viz. Tween 80 and Tween 20, having oleyl (18 carbon) and lauryl (12 carbon) hydrophobic tails, respectively as structure .

A density functional theory investigation of the ...

structure below the Verwey transition temperature), while there are only few reports on the high-temperature cubic Fd m3 phase. However, it is the structure at ambient tem-perature that is relevant in the actual operating conditions for many of the applications of magnetite [15]; therefore, a detailed understanding of the physical and chemical ...

A density functional theory investigation of the ...

Magnetite has a cubic inverse spinel structure (space group ) at room temperature with 8 formula units (f.u.) in the conventional unit cell as shown in figure figure1. 1. Its chemical formula, often written as [Fe 3+ ] A [Fe 3+,Fe 2+ ] B O 4, indicates that the tetrahedral sites denoted as A are occupied by ferric ions while octahedral sites ...

The Verwey structure of a natural magnetite - Chemical ...

Structure refinement demonstrates that the natural sample has the same complex electronic order as pure synthetic magnetite, with only minor reductions of orbital and trimeron distortions. Chemical analysis shows that the natural sample contains dopants such as Al, Si, Mg and Mn at comparable concentrations to extraterrestrial magnetites, for ...

Direct Determination of Atomic Structure and Magnetic ...

Clarifying how the atomic structure of interfaces/boundaries in materials affects the magnetic coupling nature across them is of significant academic value and will facilitate the development of state-of-the-art magnetic devices. Here, by combining atomic-resolution transmission electron microscopy, atomistic spin-polarized first-principles calculations, and differential phase contrast imaging ...

Charge order in the Verwey structure of magnetite | CSEC

Here we report the full low-temperature superstructure of magnetite, determined by high-energy X-ray diffraction from an almost single-domain, 40-micrometre grain, and identify the emergent order. The acentric structure is described by a superposition of 168 atomic displacement waves (frozen phonon modes), all with amplitudes of less than 0.24 ...

Effect of crystal defects and internal stress on the ...

Domain structures in magnetite are very sensitive to crystal imperfections, which play a major role in hysteresis and remanence by hindering the motion of domain walls. Using the Bitter colloid technique, we have observed spike and closure domains of the style predicted by Néel [1944] around nonmagnetic inclusions, chemically altered regions ...

Magnetite Mineral Data

Wechsler B A, Lindsley D H, Prewitt C T, American Mineralogist, 69 (1984) p.754-770, Crystal structure and cation distribution in titanomagnetites (Fe3-xTixO4), MT100-1350 View Additional jPOWD Structure files for Magnetite

Electronic Structure and Vibrational Spectra of Magnetite ...

The electronic structure, crystal structure and infra‐red conductivity of magnetite have been calculated using hybrid density functional methods. The crystal structure was calculated using a conjug...

Soft X-ray Spectroscopy Study of the Electronic Structure ...

The crystal structure of magnetite nanoparticles may be transformed to maghemite by complete oxidation, but under many relevant conditions the oxidation is partial, creating a mixed-valence material with structural and electronic properties that are poorly characterized. We used X-ray diffraction, Fe K-edge extended X-ray absorption fine ...

Structure, Morphology, and Crystal Growth of Bacterial ...

Abstract. The biological synthesis of the mixed-valence iron oxide magnetite (Fe 3 O 4) poses several fascinating and intriguing questions for the solid state and materials scientist.Preparation of magnetite in the laboratory requires an experimental regime which .

Soft X-ray Spectroscopy Study of the Electronic Structure ...

The crystal structure of magnetite nanoparticles may be transformed to maghemite by complete oxidation, but under many relevant conditions the oxidation is partial, creating a mixed-valence material with structural and electronic properties that are poorly characterized. We used X-ray diffraction, Fe K-edge extended X-ray absorption fine ...

Maghemite - Wikipedia

Maghemite (Fe 2 O 3, γ-Fe 2 O 3) is a member of the family of iron oxides.It has the same spinel ferrite structure as magnetite and is also ferrimagnetic.. Maghemite can be considered as an Fe(II)-deficient magnetite with formula [ ] where represents a vacancy, A indicates tetrahedral and B .

Structure-function studies of the magnetite ...

Our determined structure shows an alpha-helical fold for MamC-MIL with highly charged surfaces. Additionally, the MamC-MIL induces the formation of larger magnetite crystals compared to protein-free and inert biomineralization protein control experiments.

Soft X-ray Spectroscopy Study of the Electronic Structure ...

The crystal structure of magnetite nanoparticles may be transformed to maghemite by complete oxidation, but under many relevant conditions the oxidation is partial, creating a mixed-valence material with structural and electronic properties that are poorly characterized. We used X-ray diffraction, Fe K-edge extended X-ray absorption fine structure (EXAFS) spectroscopy, and soft X-ray ...

A density functional theory investigation of the ...

Magnetite has a cubic inverse spinel structure (space group ) at room temperature with 8 formula units (f.u.) in the conventional unit cell as shown in figure figure1. 1. Its chemical formula, often written as [Fe 3+ ] A [Fe 3+,Fe 2+ ] B O 4, indicates that the tetrahedral sites denoted as A are occupied by ferric ions while octahedral sites ...

Magnetite: The mineral Magnetite information and pictures

Magnetite is an important ore of iron. Well formed crystals are popular among mineral collectors, and the magnetic Lodestone variety is frequently sold in hobby shops to amateur collectors. Magnetite is also of significant interest to the science community due to its strong magnetic properties.

Structure and Formation of the Magnetite-Bearing Cap of ...

Abstract. Scanning electron microscopy was employed to study the ultrastructure of the magnetite-bearing cap in mature tricuspid teeth of four chiton species: Lepidochitona cinerea, Mopalia muscosa, Katharina tunicata, and Cryptochiton stelleri.The cap is composed of parallel rod-shaped units.

Magnetite - Wikipedia

Crystal structure. The chemical composition of magnetite is Fe 2+ Fe 2 3+ O 4 2−. The main details of its structure were established in 1915. It was one of the first crystal structures to be obtained using X-ray diffraction. The structure is inverse spinel, with O 2− ions forming a face-centered cubic lattice and iron cations occupying ...

[1205.1842] Ligand effects on the electronic structure and ...

5/8/2012· Abstract: We address the effect of functionalization on the electronic and magnetic properties of magnetite surface as an indicator of the same properties in nanoparticles too big for a direct ab-initio approach. Using well-established methods and references (namely LDA+U on magnetite surfaces) we could verify the validity of our approach, and using two typical ligands, dopamine and citrate ...

Magnetite : structure, properties, and applications (eBook ...

magnetite: structure, properties and applications --magnetite: structure, properties and applications --contents --preface --magnetite: the story of the mineral�s formation and stability --abstract --1. introduction to the unique mineral magnetite --2. magnetite in the solar system --3. conditions of the stability of iron oxides --4.

Effect of crystal defects and internal stress on the ...

Domain structures in magnetite are very sensitive to crystal imperfections, which play a major role in hysteresis and remanence by hindering the motion of domain walls. Using the Bitter colloid technique, we have observed spike and closure domains of the style predicted by Néel [1944] around nonmagnetic inclusions, chemically altered regions ...

Direct Determination of Atomic Structure and Magnetic ...

Clarifying how the atomic structure of interfaces/boundaries in materials affects the magnetic coupling nature across them is of significant academic value and will facilitate the development of state-of-the-art magnetic devices. Here, by combining atomic-resolution transmission electron microscopy, atomistic spin-polarized first-principles calculations, and differential phase contrast imaging ...

Magnetite - University of Wisconsin–Madison

Magnetite Mineral Description. Magnetite is an oxide mineral with structural formula [Fe 2+ (Fe 3+) 2 O 4] having the spinel structure.Other minerals in the series include magnesioferrite [Mg 2+ (Fe 3+) 2 O 4], franklinite [Zn 2+ (Fe 3+) 2 O 4] and jacobsite [Mn 2+ (Fe 3+) 2 O 4].The structure of magnetite consists of a closed-packed oxygen arrangement with the divalent Fe 2+ ion in ...