scholarly journals Field-induced metal-to-insulator transition and colossal anisotropic magnetoresistance in a nearly Dirac material EuMnSb2

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Z. L. Sun ◽  
A. F. Wang ◽  
H. M. Mu ◽  
H. H. Wang ◽  
Z. F. Wang ◽  
...  
Keyword(s):  
Electrical Transport ◽  
Density Functional ◽  
Degrees Of Freedom ◽  
Density Functional Theory Calculations ◽  
Insulator Transition ◽  
Anisotropic Magnetoresistance ◽  
Functional Theory ◽  
Magnetic Structures ◽  
Metal To Insulator Transition ◽  
Indirect Band Gap

AbstractRealizing applicably appreciated spintronic functionalities basing on the coupling between charge and spin degrees of freedom is still a challenge. For example, the anisotropic magnetoresistance (AMR) effect can be utilized to read out the information stored in magnetic structures. However, the application of AMR in antiferromagnet-based spintronics is usually hindered by the small AMR value. Here, we discover a colossal AMR with its value reaching 1.84 × 106% at 2 K, which stems from the field-induced metal-to-insulator transition (MIT), in a nearly Dirac material EuMnSb2. Density functional theory calculations identify a Dirac-like band around the Y point that depends strongly on the spin–orbit coupling and dominates the electrical transport. The indirect band gap at the Fermi level evolves with magnetic structure of Eu2+ moments, consequently giving rise to the field-induced MIT and the colossal AMR. Our results suggest that the antiferromagnetic topological materials can serve as a fertile ground for spintronics applications.

A computational study of hydrogen doping induced metal-to-insulator transition in CaFeO3, SrFeO3, BaFeO3 and SmMnO3

2019 ◽  
Vol 21 (45) ◽  
pp. 25397-25405
Author(s):  
Shukai Yao ◽  
Pilsun Yoo ◽  
Peilin Liao
Keyword(s):  
Density Functional Theory ◽  
Transition Metal ◽  
First Principles ◽  
Density Functional ◽  
Computational Study ◽  
Density Functional Theory Calculations ◽  
Functional Theory ◽  
Hydrogen Doping ◽  
Gap Opening ◽  
Metal To Insulator Transition

First principles density functional theory calculations were performed to identify transition metal perovskites CaFeO3, SrFeO3, BaFeO3 and SmMnO3 as promising candidates with large band gap opening upon hydrogen doping.

scholarly journals Electron Transfer to CO2 during Adsorption at the Metal | Solution Interface

2019 ◽  
Author(s):  
Michal Bajdich ◽  
Meredith Fields ◽  
Leanne D. Chen ◽  
Robert B. Sandberg ◽  
Karen Chan ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Density Functional ◽  
Degrees Of Freedom ◽  
Adsorption Process ◽  
Density Functional Theory Calculations ◽  
High Rate ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
Solution Interface

<i>We estimate the rate of electron transfer to CO<sub>2</sub> at the Au(211)|water interface during adsorption in an electrochemical environment under negative potentials. Based on density functional theory calculations at the generalized gradient approximation, hybrid, and GW levels of theory, we find electron transfer to adsorbed *CO<sub>2</sub> to be very facile. This high rate of transfer is estimated by the energy distribution of the adsorbate-induced density of states as well as from the interaction between diabatic states representing neutral and negatively charged CO<sub>2</sub>. Up to 0.54 electrons is transferred to CO<sub>2</sub>, and this charge adiabatically increases with the bending angle to a lower limit of 140°. We conclude that this rate of electron transfer is extremely fast compared to the timescale of the nuclear degrees of freedom, that is, the adsorption process</i><br>

scholarly journals Facile Electron Transfer to CO2 during Adsorption at the Metal | Solution Interface

2019 ◽  
Author(s):  
Joseph Gauthier ◽  
Meredith Fields ◽  
Michal Bajdich ◽  
Leanne D. Chen ◽  
Robert B. Sandberg ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Density Functional ◽  
Degrees Of Freedom ◽  
Adsorption Process ◽  
Density Functional Theory Calculations ◽  
High Rate ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
Solution Interface

<i>We estimate the rate of electron transfer to CO2 at the Au (211)|water interface during adsorption in an electrochemical environment under reducing potentials. Based on density functional theory calculations at the generalized gradient approximation and hybrid levels of theory, we find electron transfer to adsorbed *CO2 to be very facile. This high rate of transfer is estimated by the energy distribution of the adsorbate-induced density of states as well as from the interaction between diabatic states representing neutral and negatively charged CO2. Up to 0.62 electrons are transferred to CO2, and this charge adiabatically increases with the bending angle to a lower limit of 137°. We conclude that this rate of electron transfer is extremely fast compared to the timescale of the nuclear degrees of freedom, that is, the adsorption process.</i><br>

The Density Functional Study of Electronic Properties for Bismuth Aluminate

2013 ◽  
Vol 873 ◽  
pp. 877-882
Author(s):  
Lian Wei Shan ◽  
Wei Li ◽  
Rui Fang ◽  
Li Min Dong ◽  
Zhi Dong Han ◽  
...  
Keyword(s):  
Band Gap ◽  
Conduction Band ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Functional Study ◽  
Functional Theory ◽  
Interaction Range ◽  
Plane Wave Method ◽  
The Density Functional Theory ◽  
Indirect Band Gap

In this paper, the density functional theory calculations on the electronic structure of BiAlO3 by using ultrasoft pseudopotential plane wave method are carried out. The results show that cubic and trigonal BiAlO3 are indirect band gap semiconductor. And their conduction band is 0.70 and 1.49 eV, respectively. The broadening antibonding interaction range in conduction band is found. It is largely responsible for the decrease in the band gap of cubic BiAlO3. It can be also found that the CB width is obviously narrowed, while the VB width is slightly broadened.

scholarly journals Manganese oxalates - structure-based Insights

2018 ◽  
Vol 16 (1) ◽  
pp. 1176-1183 ◽  
Author(s):  
Miroslava Nedyalkova ◽  
Vladislav Antonov
Keyword(s):  
First Principles ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
First Principles Calculations ◽  
Dynamic Simulations ◽  
Functional Theory ◽  
Augmented Plane Wave ◽  
Magnetic Structures ◽  
Nmr Parameters ◽  
Crystal And Magnetic Structures

AbstractWe have investigated the crystal and magnetic structures of α -MnC2O4·2H2O and γ-MnC2O4·2H2O by the frame of density functional theory calculations and the augmented plane wave approach as implemented in the WIEN2k code. We also present a generally applicable approach step-wise dehydration process of MnC2O4·3H2O based on molecular dynamic simulations. Also, first principles calculations of NMR parameters along with the magnetic susceptibility were performed to reveal new insights into a quite exotic behavior which hampered the experimental way once by the domination of large paramagnetic shift of the d-electrons. The proposed approach paves the way for setting possible widenings by the implementation of computational strategies for such type of systems.

scholarly journals Facile Electron Transfer to CO2 during Adsorption at the Metal | Solution Interface

2019 ◽  
Author(s):  
Joseph Gauthier ◽  
Meredith Fields ◽  
Michal Bajdich ◽  
Leanne D. Chen ◽  
Robert B. Sandberg ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Density Functional ◽  
Degrees Of Freedom ◽  
Adsorption Process ◽  
Density Functional Theory Calculations ◽  
High Rate ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
Solution Interface

<i>We estimate the rate of electron transfer to CO2 at the Au (211)|water interface during adsorption in an electrochemical environment under reducing potentials. Based on density functional theory calculations at the generalized gradient approximation and hybrid levels of theory, we find electron transfer to adsorbed *CO2 to be very facile. This high rate of transfer is estimated by the energy distribution of the adsorbate-induced density of states as well as from the interaction between diabatic states representing neutral and negatively charged CO2. Up to 0.62 electrons are transferred to CO2, and this charge adiabatically increases with the bending angle to a lower limit of 137°. We conclude that this rate of electron transfer is extremely fast compared to the timescale of the nuclear degrees of freedom, that is, the adsorption process.</i><br>

On the Linear Geometry of Lanthanide Hydroxide (Ln—OH, Ln=La-Lu)

2019 ◽  
Author(s):  
Hassan Harb ◽  
Lee Thompson ◽  
Hrant Hratchian
Keyword(s):  
Triple Bond ◽  
Density Functional ◽  
Valence Electron ◽  
Density Functional Theory Calculations ◽  
Electron Configuration ◽  
Functional Theory ◽  
Key Species ◽  
Pi Orbitals ◽  
Lanthanide Hydroxide ◽  
Linear Geometry

Lanthanide hydroxides are key species in a variety of catalytic processes and in the preparation of corresponding oxides. This work explores the fundamental structure and bonding of the simplest lanthanide hydroxide, LnOH (Ln=La-Lu), using density functional theory calculations. Interestingly, the calculations predict that all structures of this series will be linear. Furthermore, these results indicate a valence electron configuration featuring an occupied sigma orbital and two occupied pi orbitals for all LnOH compounds, suggesting that the lanthanide-hydroxide bond is best characterized as a covalent triple bond.

On the Linear Geometry of Lanthanide Hydroxide (Ln—OH, Ln=La-Lu)

2019 ◽  
Author(s):  
Hassan Harb ◽  
Lee Thompson ◽  
Hrant Hratchian
Keyword(s):  
Triple Bond ◽  
Density Functional ◽  
Valence Electron ◽  
Density Functional Theory Calculations ◽  
Electron Configuration ◽  
Functional Theory ◽  
Key Species ◽  
Pi Orbitals ◽  
Lanthanide Hydroxide ◽  
Linear Geometry

Lanthanide hydroxides are key species in a variety of catalytic processes and in the preparation of corresponding oxides. This work explores the fundamental structure and bonding of the simplest lanthanide hydroxide, LnOH (Ln=La-Lu), using density functional theory calculations. Interestingly, the calculations predict that all structures of this series will be linear. Furthermore, these results indicate a valence electron configuration featuring an occupied sigma orbital and two occupied pi orbitals for all LnOH compounds, suggesting that the lanthanide-hydroxide bond is best characterized as a covalent triple bond.

Sign in / Sign up

Export Citation Format

Share Document