Field-induced canting of magnetic moments in GdCo5 at finite temperature: first-principles calculations and high-field measurements

The electronic structure and spin polarization properties of pentagonal structure PdSe2 doped with transition metal atoms are studied through first- principles calculations. The theoretical investigations show that the band gap of the PdSe2 monolayer decreases after introducing Cr, Mn, Fe and Co dopants. The projected densities of states show that p-d orbital couplings between the transition metal atoms and PdSe2 generate new spin nondegenerate states near the Fermi level which make the system spin polarized. The calculated magnetic moments, spin density distributions and charge transfer of the systems suggest that the spin polarization in Cr-doped PdSe2 will be the biggest. Our work shows that the properties of PdSe2 can be modified by doping transition metal atoms, which provides opportunity for the applications of PdSe2 in electronics and spintronics.

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Magnetism and Half-Metallicity in (100) Surface of Inverse Heusler Mn2CoSb

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1015.377 ◽

2014 ◽

Vol 1015 ◽

pp. 377-380

Author(s):

Tao Chen ◽

Ying Chen ◽

Yin Zhou ◽

Hong Chen

Keyword(s):

Density Functional Theory ◽

Magnetic Properties ◽

First Principles ◽

Heusler Alloy ◽

Density Functional ◽

Magnetic Moments ◽

Surface States ◽

First Principles Calculations ◽

Half Metallicity ◽

Functional Theory

Using the first-principles calculations within density functional theory (DFT), we investigated the electronic and magnetic properties of (100) surface of inverse Heusler alloy Mn2CoSb with five different terminations. Our work reveals that the surface Mn atom moves to vacuum while surface Co atom moves to slab. Moreover, duo to the reason that the surface atom lost half of the nearest atoms with respect to the bulk phase, resulting in the decrease of hybridization, the atom-resolved spin magnetic moments of surface atoms are enhanced. Further investigation on DOS and PDOS showed that half-metallicity was preserved only in SbSb-termination while was destroyed in MnCo-, MnSb-, MnMn-, and CoCo-termination due to the appearance of surface states.

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STABLE STRUCTURES, ELECTRIC AND MAGNETIC PROPERTIES OF NANOPARTICLES COn(n = 1-6) CLUSTERS: FIRST-PRINCIPLES CALCULATIONS

International Journal of Modern Physics B ◽

10.1142/s0217979213620075 ◽

2013 ◽

Vol 27 (15) ◽

pp. 1362007

Author(s):

JUN LIU ◽

SHENG-BIAO TAN ◽

HUI-NING DONG

Keyword(s):

Magnetic Properties ◽

Ground State ◽

First Principles ◽

Lower Energy ◽

Magnetic Moments ◽

Molecular Orbitals ◽

First Principles Calculations ◽

Half Metallicity ◽

Ground State Structures ◽

Stable Structures

The ground state geometric structures of the nanoparticles or clusters CO n(n = 1-6) were given based on the first-principles calculations. Then the magnetic properties of the clusters CO n(n = 1-6) and ( CO n)-2(n = 1-6) were calculated in system. Results show that their ground state structures are closely related to the numbers of O-ions. These clusters have no magnetic moments and half-metallicity if they are electroneutral. However, they have magnetic moments if they have positive or negative charges. The total magnetic moments of the clusters ( CO n)-2(n = 1-6, but n≠3) are all 2.0000 μB, and all their ions have contributions to the total magnetic moments. The main reason is that the molecular orbitals with lower energy filled with paired electrons and the molecular orbitals with higher energy are occupied by two electrons in parallel.

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Ab-Initio Study of the Electronic and Magnetic Properties of Boron- and Nitrogen-Doped Penta-Graphene

Nanomaterials ◽

10.3390/nano10040816 ◽

2020 ◽

Vol 10 (4) ◽

pp. 816 ◽

Cited By ~ 1

Author(s):

Chao Zhang ◽

Yu Cao ◽

Xing Dai ◽

Xian-Yong Ding ◽

Leilei Chen ◽

...

Keyword(s):

Magnetic Properties ◽

Charge Transfer ◽

First Principles ◽

Magnetic Moments ◽

First Principles Calculations ◽

Electronic Band ◽

Magnetic Devices ◽

Spin Polarized ◽

Electronic Band Gap ◽

Transfer Mechanisms

First-principles calculations were performed to investigate the effects of boron/nitrogen dopant on the geometry, electronic structure and magnetic properties of the penta-graphene system. It was found that the electronic band gap of penta-graphene could be tuned and varied between 1.88 and 2.12 eV depending on the type and location of the substitution. Moreover, the introduction of dopant could cause spin polarization and lead to the emergence of local magnetic moments. The main origin of the magnetic moment was analyzed and discussed by the examination of the spin-polarized charge density. Furthermore, the direction of charge transfer between the dopant and host atoms could be attributed to the competition between the charge polarization and the atomic electronegativity. Two charge-transfer mechanisms worked together to determine which atoms obtained electrons. These results provide the possibility of modifying penta-graphene by doping, making it suitable for future applications in the field of optoelectronic and magnetic devices.

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Effects of finite temperature on the surface energy in Al alloys from first-principles calculations

Applied Surface Science ◽

10.1016/j.apsusc.2019.02.127 ◽

2019 ◽

Vol 479 ◽

pp. 499-505

Author(s):

Zhipeng Wang ◽

Dongchu Chen ◽

Qihong Fang ◽

Hong Chen ◽

Touwen Fan ◽

...

Keyword(s):

Surface Energy ◽

First Principles ◽

Finite Temperature ◽

Al Alloys ◽

First Principles Calculations

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Phase Stability and Magnetic Properties of Mn3Z (Z = Al, Ga, In, Tl, Ge, Sn, Pb) Heusler Alloys

Applied Sciences ◽

10.3390/app9050964 ◽

2019 ◽

Vol 9 (5) ◽

pp. 964 ◽

Cited By ~ 4

Author(s):

Haopeng Zhang ◽

Wenbin Liu ◽

Tingting Lin ◽

Wenhong Wang ◽

Guodong Liu

Keyword(s):

Magnetic Properties ◽

Structural Stability ◽

Phase Stability ◽

First Principles ◽

Magnetic Moments ◽

Heusler Alloys ◽

Atomic Radius ◽

Tetragonal Distortion ◽

Stable Phase ◽

First Principles Calculations

The structural stability and magnetic properties of the cubic and tetragonal phases of Mn3Z (Z = Ga, In, Tl, Ge, Sn, Pb) Heusler alloys are studied by using first-principles calculations. It is found that with the increasing of the atomic radius of Z atom, the more stable phase varies from the cubic to the tetragonal structure. With increasing tetragonal distortion, the magnetic moments of Mn (A/C and B) atoms change in a regular way, which can be traced back to the change of the relative distance and the covalent hybridization between the atoms.

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New high pressure polymorph of the CaSi2 compound with Laves structure

Modern Physics Letters B ◽

10.1142/s0217984914500808 ◽

2014 ◽

Vol 28 (10) ◽

pp. 1450080

Author(s):

Hichem Bouderba ◽

Raouf Beddiaf

Keyword(s):

High Pressure ◽

First Principles ◽

Finite Temperature ◽

First Principles Calculations ◽

Laves Phases

In the present work, based on first-principles calculations, we show that it is possible to obtain a new high pressure polymorph of the CaSi 2 compound with a Laves structure. It corresponds to the MgCu 2-type (C15) which is one of the three most important Laves phases. We also show that the two other structures, MgNi 2- and MgZn 2-types are very competitive energetically and are possible candidates for finite temperature investigations.

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Properties of Iron Atoms at Grain Boundaries in Fe and Fe72Al28

MRS Proceedings ◽

10.1557/proc-527-273 ◽

1998 ◽

Vol 527 ◽

Cited By ~ 3

Author(s):

O. Schneeweiss ◽

I. Turek ◽

J. Čermák ◽

P. Lejček

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Single Crystals ◽

First Principles ◽

Magnetic Moments ◽

Emission Mössbauer Spectroscopy ◽

First Principles Calculations ◽

Hyperfine Parameters ◽

Impurity Atoms ◽

Atomic Spacing

ABSTRACTLocation of diffused 57Co atoms in single crystals, bicrystals and polycrystals of pure iron and Fe72Al28alloy were investigated by means of emission Mössbauer spectroscopy. To interpret the results, first principles calculations of iron atom magnetic moments and hyper-fine field were carried out. From comparison of M6ssbauer spectra of single crystals with those of bicrystals and polycrystals, an information about grain boundary positions occupied by diffusing atoms is obtained. It is shown that about 5% of the diffusing atoms at the {112} grain boundary of iron are located at the positions either having impurity atoms in the nearest neighbourhood or characterized by larger atomic spacing in comparison with the bulk. In the Fe72Al28 a dominating portion of diffusing atoms have different surrounding than in grain volume. An enrichment of grain boundaries by aluminum could explain their hyperfine parameters.

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Structural Evolution, Redox Mechanism, and Ionic Diffusion in Rhombohedral Na2FeFe(CN)6 for Sodium-Ion Batteries: First-Principles Calculations

Journal of The Electrochemical Society ◽

10.1149/1945-7111/ac49cf ◽

2022 ◽

Author(s):

Ya-Ping Wang ◽

B. P. Hou ◽

Xin-Rui Cao ◽

Shunqing Wu ◽

Zi-Zhong Zhu

Keyword(s):

First Principles ◽

Rational Design ◽

Low Cost ◽

Magnetic Moments ◽

Three Dimensional ◽

Structural Evolution ◽

Sodium Ion ◽

High Rate ◽

Sodium Ion Batteries ◽

First Principles Calculations

Abstract Prussian blue analogs (Na2FeFe(CN)6) have been regarded as potential cathode materials for sodium-ion batteries (SIBs) due to their low-cost iron resources and open framework. Herein, the detailed first-principles calculations have been performed to investigate the electrochemical properties of NaxFeFe(CN)6 during Na ion extraction. The material undergoes a phase transition from a dense rhombohedral to open cubic structure upon half-desodiation, which is resulted from competition of the Na−N Coulomb attraction and d−π covalent bonding of Fe−N. The analyses on the density of states, magnetic moments and Bader charges of NaxFeFe(CN)6 reveal that there involve in the successive redox reactions of high-spin Fe2+/Fe3+ and low-spin Fe2+/Fe3+ couples during desodiation. Moreover, the facile three-dimensional diffusion channels for Na+ ions exhibit low diffusion barriers of 0.4 eV ~ 0.44 eV, which ensures a rapid Na+ transport in the NaxFeFe(CN)6 framework, contributing to high rate performance of the battery. This study gives a deeper understanding of the electrochemical mechanisms of NaxFeFe(CN)6 during Na+ extraction, which is beneficial for the rational design of superior PBA cathodes for SIBs.

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