First-principles study of complex ferrimagnetic states in
maghemite-related nanoparticles

a 2024

First-principles study of complex ferrimagnetic states in maghemite-related nanoparticles

BERECOVÁ, Valentína; Martin FRIÁK; Naděžda PIZÚROVÁ a Jana PAVLŮ

Základní údaje

Originální název

First-principles study of complex ferrimagnetic states in maghemite-related nanoparticles

Autoři

BERECOVÁ, Valentína; Martin FRIÁK; Naděžda PIZÚROVÁ a Jana PAVLŮ

Vydání

The 11th International Conference on Multiscale Materials Modeling (MMM11), Prague, Czech Republic, 2024

Další údaje

Jazyk

angličtina

Typ výsledku

Konferenční abstrakt

Obor

10403 Physical chemistry

Stát vydavatele

Česká republika

Utajení

není předmětem státního či obchodního tajemství

Označené pro přenos do RIV

Ano

Kód RIV

RIV/00216224:14310/24:00139100

Organizační jednotka

Přírodovědecká fakulta

Klíčová slova anglicky

quantum-mechanical calculations; maghemite; magnetism; nanoparticles

Změněno: 16. 11. 2025 18:55, Mgr. Valentína Berecová

Anotace

V originále

Maghemite γ-Fe2O3 is a biocompatible ferrimagnetic mineral crystalizing in an inverse spinel lattice - it can be considered as magnetite Fe3O4 containing a high concentration of iron vacancies. The magnetic behavior of both maghemite and magnetite is similar except for the value of the magnetic moment. The magnetic moment of a magnetite is higher than that of a maghemite. In a nanoparticle form, maghemite has numerous applications, such asmagnetic resonance imaging agents, drug delivery, gas sensors, energy storage, bio-separation, purification, as well as many others profiting uses from the combination of its magnetic properties, biocompatibility and small size. As many experimental methods cannot distinguish magnetite and maghemite due to their structural similarity, we have employed quantum-mechanical calculations to study the local magnetic moments of individual atoms in maghemite-related nanoparticles. Motivated by results obtained for the bulk maghemite γ-Fe2O3, our calculations of nanoparticles started from the ferrimagnetic state when tetrahedrally and octahedrally O-coordinated Fe sublattices exhibit mutually opposite orientations of local magnetic moments. Importantly, our calculations indicate that the nanoparticle surfaces result in a much more complex magnetic state characterized by a „nested“ ferrimagnetism. It is characterized by local magnetic moments of Fe atoms with mutually opposite orientations appearing even within each of the two (tetrahedral or octahedral) sublattices.

Návaznosti

90254, velká výzkumná infrastruktura

Název: e-INFRA CZ II

Citovat

BERECOVÁ, Valentína; Martin FRIÁK; Naděžda PIZÚROVÁ a Jana PAVLŮ. First-principles study of complex ferrimagnetic states in maghemite-related nanoparticles. In The 11th International Conference on Multiscale Materials Modeling (MMM11), Prague, Czech Republic. 2024.

@proceedings{2484889,
   author = {Berecová, Valentína and Friák, Martin and Pizúrová, Naděžda and Pavlů, Jana},
   booktitle = {The 11th International Conference on Multiscale Materials Modeling (MMM11), Prague, Czech Republic},
   keywords = {quantum-mechanical calculations; maghemite; magnetism; nanoparticles},
   language = {eng},
   title = {First-principles study of complex ferrimagnetic states in maghemite-related nanoparticles},
   year = {2024}
}

TY  - CONF
ID  - 2484889
AU  - Berecová, Valentína - Friák, Martin - Pizúrová, Naděžda - Pavlů, Jana
PY  - 2024
TI  - First-principles study of complex ferrimagnetic states in maghemite-related nanoparticles
KW  - quantum-mechanical calculations
KW  - maghemite
KW  - magnetism
KW  - nanoparticles
N2  - Maghemite γ-Fe2O3 is a biocompatible ferrimagnetic mineral crystalizing in an inverse spinel lattice - it can be considered as magnetite Fe3O4 containing a high concentration of iron vacancies. The magnetic behavior of both maghemite and magnetite is similar except for the value of the magnetic moment. The magnetic moment of a magnetite is higher than that of a maghemite. In a nanoparticle form, maghemite has numerous applications, such asmagnetic resonance imaging agents, drug delivery, gas sensors, energy storage, bio-separation, purification, as well as many others profiting uses from the combination of its magnetic properties, biocompatibility and small size. As many experimental methods cannot distinguish magnetite and maghemite due to their structural similarity, we have employed quantum-mechanical calculations to study the local magnetic moments of individual atoms in maghemite-related nanoparticles. Motivated by results obtained for the bulk maghemite γ-Fe2O3, our calculations of nanoparticles started from the ferrimagnetic state when tetrahedrally and octahedrally O-coordinated Fe sublattices exhibit mutually opposite orientations of local magnetic moments. Importantly, our calculations indicate that the nanoparticle surfaces result in a much more complex magnetic state characterized by a „nested“ ferrimagnetism. It is characterized by local magnetic moments of Fe atoms with mutually opposite orientations appearing even within each of the two (tetrahedral or octahedral) sublattices.
ER  -

BERECOVÁ, Valentína; Martin FRIÁK; Naděžda PIZÚROVÁ a Jana PAVLŮ. First-principles study of complex ferrimagnetic states in maghemite-related nanoparticles. In \textit{The 11th International Conference on Multiscale Materials Modeling (MMM11), Prague, Czech Republic}. 2024.

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