First-Principles Prediction of Skyrmionic Phase Behavior in GdFe$_2$ Films Capped by 4$D$ and 5$D$ Transition Metals

In atomic GdFe$_2$ films capped by 4$d$ and 5$d$ transition metals, we show that skyrmions with extremely reduced diameters of a smaller than 12 nm can occur. The Dzyaloshinskii-Moriya interaction (DMI), exchange energy, and the magnetocrystalline anisotropy (MCA) energy were investigated based on density functional theory. Since DMI and MCA are caused by spin-orbit coupling, they are increased with 5$d$ capping layers compared to films capped by 4$d$ transition metal. We discovered a skyrmion phase by using atomistic spin dynamics simulations at small magnetic fields of $\sim$ 1 T. A ground state that a spin spiral phase is remained even at zero magnetic field for both films with 4$d$ and 5$d$ capping layers.

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First-Principles Prediction of Skyrmionic Phase Behavior in GdFe2 Films Capped by 4d and 5d Transition Metals

Applied Sciences ◽

10.3390/app9040630 ◽

2019 ◽

Vol 9 (4) ◽

pp. 630 ◽

Cited By ~ 3

Author(s):

Soyoung Jekal ◽

Andreas Danilo ◽

Dao Phuong ◽

Xiao Zheng

Keyword(s):

Transition Metals ◽

Density Functional ◽

Spin Dynamic ◽

Zero Magnetic Field ◽

Spin Orbit Coupling ◽

Dynamic Simulations ◽

Functional Theory ◽

Spin Spiral ◽

Moriya Interaction ◽

Spiral Phase

In atomic GdFe 2 films capped by 4d and 5d transition metals, we show that skyrmions with diameters smaller than 12 nm can emerge. The Dzyaloshinskii–Moriya interaction (DMI), exchange energy, and the magnetocrystalline anisotropy (MCA) energy were investigated based on density functional theory. Since DMI and MCA are caused by spin–orbit coupling (SOC), they are increased with 5d capping layers which exhibit strong SOC strength. We discover a skyrmion phase by using atomistic spin dynamic simulations at small magnetic fields of ∼1 T. In addition, a ground state that a spin spiral phase is remained even at zero magnetic field for both films with 4d and 5d capping layers.

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First-Principles Prediction of Skyrmionic Phase Behavior in GdFe$_2$ Films Capped by 4$D$ and 5$D$ Transition Metals

10.20944/preprints201901.0242.v2 ◽

2019 ◽

Author(s):

Soyoung Jekal ◽

Andreas Danilo ◽

Dao Phoung ◽

Xiao Zheng

Keyword(s):

Transition Metals ◽

Density Functional ◽

Spin Dynamic ◽

Zero Magnetic Field ◽

Spin Orbit Coupling ◽

Dynamic Simulations ◽

Functional Theory ◽

Spin Spiral ◽

Moriya Interaction ◽

Spiral Phase

In atomic GdFe$_2$ films capped by 4$d$ and 5$d$ transition metals, we show that skyrmions with diameters smaller than 12 nm can emerge. The Dzyaloshinskii--Moriya interaction (DMI), exchange energy, and the magnetocrystalline anisotropy (MCA) energy were investigated based on density functional theory. Since DMI and MCA are caused by spin--orbit coupling (SOC), they are increased with 5$d$ capping layers which exhibit strong SOC strength. We discover a skyrmion phase by using atomistic spin dynamic simulations at small magnetic fields of $\sim$1 T. In addition, a ground state that a spin spiral phase is remained even at zero magnetic field for both films with 4$d$ and 5$d$ capping layers.

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The Damping Term, from First Principles

10.1093/oso/9780198788669.003.0006 ◽

2017 ◽

Author(s):

Olle Eriksson ◽

Anders Bergman ◽

Lars Bergqvist ◽

Johan Hellsvik

Keyword(s):

Density Functional Theory ◽

First Principles ◽

Density Functional ◽

Spin Dynamics ◽

Damping Term ◽

Functional Theory ◽

Basic Principles ◽

Sham Equation ◽

Damping Parameter ◽

Simulation Cell

In the previous chapters we described the basic principles of density functional theory, gave examples of how accurate it is to describe static magnetic properties in general, and derived from this basis the master equation for atomistic spin-dynamics; the SLL (or SLLG) equation. However, one term was not described in these chapters, namely the damping parameter. This parameter is a crucial one in the SLL (or SLLG) equation, since it allows for energy and angular momentum to dissipate from the simulation cell. The damping parameter can be evaluated from density functional theory, and the Kohn-Sham equation, and it is possible to determine its value experimentally. This chapter covers in detail the theoretical aspects of how to calculate theoretically the damping parameter. Chapter 8 is focused, among other things, on the experimental detection of the damping, using ferromagnetic resonance.

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Graphene adlayer growth between nonepitaxial graphene and Ni(111) substrate: a promising theoretical scheme

Physical Chemistry Chemical Physics ◽

10.1039/d0cp04667a ◽

2020 ◽

Author(s):

Lijuan Meng ◽

Jinlian Lu ◽

Yujie Bai ◽

Lili Liu ◽

Tang Jingyi ◽

...

Keyword(s):

Molecular Dynamics ◽

Density Functional Theory ◽

Chemical Vapor Deposition ◽

Molecular Dynamics Simulations ◽

Vapor Deposition ◽

Density Functional ◽

Chemical Vapor ◽

Density Functional Theory Calculations ◽

Functional Theory ◽

Dynamics Simulations

Understanding the fundamentals of chemical vapor deposition bilayer graphene growth is crucial for its synthesis. By employing density functional theory calculations and classical molecular dynamics simulations, we have investigated the...

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H2 Transformations on Graphene Supported Palladium Cluster: DFT-MD Simulations and NEB Calculations

Catalysts ◽

10.3390/catal10111306 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1306

Author(s):

Francesco Ferrante ◽

Antonio Prestianni ◽

Marco Bertini ◽

Dario Duca

Keyword(s):

Atomic Hydrogen ◽

Density Functional ◽

Hydrogen Molecule ◽

Md Simulations ◽

Vacant Site ◽

Functional Theory ◽

H2 Adsorption ◽

Palladium Cluster ◽

Supported Palladium ◽

Dynamics Simulations

Molecular dynamics simulations based on density functional theory were employed to investigate the fate of a hydrogen molecule shot with different kinetic energy toward a hydrogenated palladium cluster anchored on the vacant site of a defective graphene sheet. Hits resulting in H2 adsorption occur until the cluster is fully saturated. The influence of H content over Pd with respect to atomic hydrogen spillover onto graphene was investigated. Calculated energy barriers of ca. 1.6 eV for H-spillover suggest that the investigated Pd/graphene system is a good candidate for hydrogen storage.

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Spin–orbit coupling effect on Au–C60 interaction: A density functional theory study

Chemical Physics ◽

10.1016/j.chemphys.2011.06.013 ◽

2012 ◽

Vol 395 ◽

pp. 82-86 ◽

Cited By ~ 7

Author(s):

Qun Zeng ◽

Xiang Chu ◽

Mingli Yang ◽

De-Yin Wu

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Coupling Effect ◽

Orbit Coupling ◽

Spin Orbit Coupling ◽

Spin Orbit ◽

Density Functional Theory Study ◽

Functional Theory

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RDX Compression, α→ γ Phase Transition, and Shock Hugoniot Calculations from Density-Functional-Theory-Based Molecular Dynamics Simulations

The Journal of Physical Chemistry C ◽

10.1021/acs.jpcc.6b06415 ◽

2016 ◽

Vol 120 (35) ◽

pp. 19547-19557 ◽

Cited By ~ 4

Author(s):

Dan C. Sorescu ◽

Betsy M. Rice

Keyword(s):

Phase Transition ◽

Molecular Dynamics ◽

Density Functional Theory ◽

Molecular Dynamics Simulations ◽

Density Functional ◽

Functional Theory ◽

Shock Hugoniot ◽

Dynamics Simulations

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Threshold defect production in silicon determined by density functional theory molecular dynamics simulations

Physical Review B ◽

10.1103/physrevb.78.045202 ◽

2008 ◽

Vol 78 (4) ◽

Cited By ~ 105

Author(s):

E. Holmström ◽

A. Kuronen ◽

K. Nordlund

Keyword(s):

Molecular Dynamics ◽

Density Functional Theory ◽

Molecular Dynamics Simulations ◽

Density Functional ◽

Defect Production ◽

Functional Theory ◽

Dynamics Simulations

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A Free Aluminylene with Diverse σ-Donating and Doubly σ/π-Accepting Ligand Features for Transition Metals

10.33774/chemrxiv-2021-pk4xk-v2 ◽

2021 ◽

Author(s):

Xin Zhang ◽

Liu Leo Liu

Keyword(s):

Density Functional Theory ◽

Coordination Chemistry ◽

Transition Metals ◽

Electronic Structures ◽

Ligand Exchange ◽

Density Functional ◽

Reduction Reaction ◽

Functional Theory ◽

Metal Centers ◽

Coordination Behavior

We report herein the synthesis, characterization, and coordination chemistry of a free N-aluminylene, namely a carbazolylaluminylene 2b. This species is prepared via a reduction reaction of the corresponding carbazolyl aluminium diiodide. The coordination behavior of 2b towards transition metal centers (W, Cr) is shown to afford a series of novel aluminylene complexes 3-6 with diverse coordination modes. We demonstrate that the Al center in 2b can behave as: 1. a σ-donating and doubly π-accepting ligand; 2. a σ-donating, σ-accepting and π-accepting ligand; and 3. a σ-donating and doubly σ-accepting ligand. Additionally, we show ligand exchange at the aluminylene center providing access to the modulation of electronic properties of transition metals without changing the coordinated atoms. Investigations of 2b with IDippCuCl (IDipp = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) show an unprecedented aluminylene-alumanyl transformation leading to a rare terminal Cu-alumanyl complex 8. The electronic structures of such complexes and the mechanism of the aluminylene-alumanyl transformation are investigated through density functional theory (DFT) calculations.

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