THE ELECTRONIC STRUCTURE AND MAGNETISM OF CrSb WITH LATTICE CONSTANTS

The electronic structure and magnetism of CrSb compounds have been studied by a periodic quantum-mechanical calculation based on density functional theory. The results show that a ferrimagnetic ordered phase of CrSb in the Zinc-blende structure (ZB) is stable with half metallic properties, whereas the antiferromagnetic phase of CrSb in the NiAs -type crystal structure is energetically favored with no-gap band. The lattice constants have significant influence on the magnetism of CrSb . The band gap and the magnetic moment of Cr atom increase with increasing lattice constant in ZB CrSb . The effects on magnetic moment in the NiAs -type crystal structure are more sensitive substantially to the change of lattice constant a as compared with that of the lattice constant c. It is found that apart from ionic or metallic bonds there are covalent bonds between Cr d and Sb p orbitals in ZB CrSb , while bonding between Cr and Sb atoms is mainly ionic or metallic in CrSb of NiAs structure.

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Electronic structure of Cr1−S (δ=0, 0.17) with NiAs-type crystal structure

Solid State Communications ◽

10.1016/s0038-1098(02)00806-2 ◽

2003 ◽

Vol 125 (5) ◽

pp. 243-246 ◽

Cited By ~ 3

Author(s):

M. Koyama ◽

H. Sato ◽

Y. Ueda ◽

C. Hirai ◽

M. Taniguchi

Keyword(s):

Crystal Structure ◽

Electronic Structure ◽

Nias Type ◽

Type Crystal

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Half-metallic properties in Co2XSn (X = Ti, V and Cr) full-Heusler compound

Modern Physics Letters B ◽

10.1142/s0217984920500281 ◽

2019 ◽

Vol 34 (02) ◽

pp. 2050028 ◽

Cited By ~ 4

Author(s):

H. Abbassa ◽

A. Labdelli ◽

S. Meskine ◽

Y. Benaissa Cherif ◽

A. Boukortt

Keyword(s):

Magnetic Moment ◽

Density Functional ◽

Heusler Alloys ◽

Electronic Band ◽

Half Metallic ◽

Lattice Constants ◽

Half Metal ◽

Wide Range ◽

Metallic Ferromagnetism ◽

Half Metallic Ferromagnetism

First-principles calculations based on density functional theory (DFT) confirm the half-metallic ferromagnetism in both [Formula: see text] and [Formula: see text], and the nearly half-metallic ferromagnetism in [Formula: see text] Heusler alloys with the [Formula: see text]-type structure [Formula: see text]. The electronic band structures and density of states (DOS) calculations of the [Formula: see text] and [Formula: see text] compounds show that the spin-up electrons are metallic, whereas the spin-down bands are semiconducting with a gap of 0.47 eV and 0.53 eV, respectively, with 0.21 eV and 0.36 eV as a spin-flip gap, respectively. The [Formula: see text] and [Formula: see text] Heusler were half-metal compounds with magnetic moment of [Formula: see text] and [Formula: see text] at the equilibrium lattice constants [Formula: see text] Å and [Formula: see text] Å, respectively, which agrees with the Slater–Pauling rule, and have 100% polarization for a wide range of lattice parameters. The [Formula: see text] is a nearly half-metal (NHF) compound with magnetic moment of [Formula: see text] and 92.9% polarization at the equilibrium lattice constants [Formula: see text] Å and acquire half-metal behavior under the pressure 16.70 GPa.

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Tunable electronic structure and magnetic moment in C2N nanoribbons with different edge functionalization atoms

Physical Chemistry Chemical Physics ◽

10.1039/c7cp01359k ◽

2017 ◽

Vol 19 (23) ◽

pp. 15021-15029 ◽

Cited By ~ 7

Author(s):

Yusheng Wang ◽

Nahong Song ◽

Min Jia ◽

Dapeng Yang ◽

Chikowore Panashe ◽

...

Keyword(s):

Density Functional Theory ◽

Magnetic Properties ◽

Electronic Structure ◽

Magnetic Moment ◽

First Principles ◽

Density Functional ◽

First Principles Calculations ◽

Functional Theory ◽

Electronic And Magnetic Properties

First principles calculations based on density functional theory were carried out to study the electronic and magnetic properties of C2N nanoribbons (C2NNRs).

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Theoretical study on the electronic structure, mechanical property, and thermal expansion of yttrium oxysulfide

International Journal of Computational Materials Science and Engineering ◽

10.1142/s2047684115500049 ◽

2015 ◽

Vol 04 (01) ◽

pp. 1550004

Author(s):

Ruipeng Gao ◽

Yefei Li

Keyword(s):

Mechanical Property ◽

Thermal Expansion ◽

Electronic Structure ◽

Bulk Modulus ◽

Density Functional ◽

Theoretical Study ◽

Spherical Shape ◽

Weak Anisotropy ◽

Covalent Bonds ◽

Very High

The electronic structure, mechanical property and thermal expansion of yttrium oxysulfide are calculated from first-principles using the theory of density functional. The calculated cohesive energy indicates its thermodynamic stable nature. From bond structure, the calculated bandgap is obtained as 2.7 eV; and strong covalent bonds exist between Y and O atoms intra 2D [ Y – O ] layer in material, while relatively weak covalent bonds also exist inter 2D [ Y – O ] layer and S atoms. From simulation, it is found that the bulk modulus is about 119.4 GPa for the elastic constants, and the bulk modulus shows weak anisotropy because the surface contours of them are close to a spherical shape. The calculated B/G clearly implies its ductile nature, and the Y 2 O 2 S phase can also be compressed easily. The temperature dependence of thermal expansions is mainly caused by the restoration of thermal energy due to lattice excitations at low temperature. When the temperature is very high, the thermal expansion coefficient increases linearly with temperature increasing. Meanwhile, the heat capacities are also calculated and discussed by thermal expansion and elasticity.

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Chirality and Magnetocaloricity in GdFeTeO6 as Compared to GdGaTeO6

Materials ◽

10.3390/ma14205954 ◽

2021 ◽

Vol 14 (20) ◽

pp. 5954

Author(s):

Elena Zvereva ◽

Tatyana Vasilchikova ◽

Maria Evstigneeva ◽

Angelica Tyureva ◽

Vladimir Nalbandyan ◽

...

Keyword(s):

Crystal Structure ◽

Density Functional Theory ◽

Density Functional ◽

Rietveld Method ◽

Density Functional Theory Calculations ◽

Antiferromagnetic Order ◽

Functional Theory ◽

Paramagnetic Behavior ◽

Weakly Coupled ◽

Type Crystal

GdFeTeO6 and GdGaTeO6 have been prepared and their structures refined by the Rietveld method. Both are superstructures of the rosiaite type (space group ). Their thermodynamic properties have been investigated by means of magnetization M and specific heat Cp measurements, evidencing the formation of the long-range antiferromagnetic order at TN = 2.4 K in the former compound and paramagnetic behavior down to 2 K in the latter compound. Large magnetocaloric effect allows considering GdFeTeO6 for the magnetic refrigeration at liquid hydrogen stage. Density functional theory calculations produce estimations of leading Gd–Gd, Gd–Fe and Fe–Fe interactions suggesting unique chiral 120° magnetic structure of Fe3+ (S = 5/2) moments and Gd3+ (J = 7/2) moments rotating in opposite directions (clockwise/anticlockwise) within weakly coupled layers of the rosiaite type crystal structure.

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Unveiling the Atomic and Electronic Structure of Stacked-Cup Carbon Nanofibers

Nanoscale Research Letters ◽

10.1186/s11671-021-03595-y ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

D. W. Boukhvalov ◽

I. S. Zhidkov ◽

A. Kiryakov ◽

J. L. Menéndez ◽

L. Fernández-García ◽

...

Keyword(s):

Electronic Structure ◽

Carbon Nanofibers ◽

Density Functional ◽

Graphene Quantum Dots ◽

Quantitative Agreement ◽

Optical Measurements ◽

Radiative Relaxation ◽

Covalent Bonds ◽

Band Spectra ◽

Valence Bands

AbstractWe report results of comprehensive experimental exploration (X-ray photoemission, Raman and optical spectroscopy) of carbon nanofibers (CNFs) in combination with first-principles modeling. Core-level spectra demonstrate prevalence of sp2 hybridization of carbon atoms in CNF with a trace amount of carbon–oxygen bonds. The density functional theory (DFT)-based calculations demonstrated no visible difference between mono- and bilayers because σ-orbitals are related to in-plane covalent bonds. The influence of the distortions on π-peak is found to be significant only for bilayers as a result of π–π interlayer bonds formation. These results are supported by both experimental Raman and XPS valence band spectra. The combination of optical measurements with a theoretical modeling indicates the formation of optically active graphene quantum dots (GQDs) in the CNF matrix, with a radiative relaxation of the excited π* state. The calculated electronic structure of these GQDs is in quantitative agreement with the measured optical transitions and provides an explanation of the absence of visible contribution from these GQDs to the measured valence bands spectra.

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Study on the Effect of Doping on Lattice Constant and Electronic Structure of Bulk AuCu by the Density Functional Theory

Journal of Multiscale Modelling ◽

10.1142/s1756973720300014 ◽

2019 ◽

Vol 11 (02) ◽

pp. 2030001 ◽

Cited By ~ 2

Author(s):

Dung Nguyen-Trong ◽

Cuong Nguyen-Chinh ◽

Van Duong-Quoc

Keyword(s):

Density Functional Theory ◽

Electronic Structure ◽

Electronic Properties ◽

Lattice Constant ◽

Density Of States ◽

Impurity Concentration ◽

Density Functional ◽

Unit Cell ◽

Functional Theory ◽

The Density Functional Theory

This paper studies the effect of GGA-PBE, GGA-PBEsol, GGA-PW91, GGA-VWN-BP, LDA-PWC, LDA-VWN parameterized exchange–correlation functionals and Cu impurity concentration on the lattice and electronic properties of bulk AuCu by the Density Functional Theory (DFT). The lattice properties are determined by the lattice constant, the unit cell volume and the total energy on unit cell. The electronic properties are determined by the band gap, the Partial Density of States (PDOS) and the total Density of States (DOS) of materials. The obtained results showed the effect of the interaction potential and the Cu impurity concentration on the lattice structure and the electronic structure of bulk AuCu.

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First-Principles Study on Electronic Structure, Elasticity, Debye Temperature and Anisotropy of Cubic KCaF3

Materials Science Forum ◽

10.4028/www.scientific.net/msf.999.109 ◽

2020 ◽

Vol 999 ◽

pp. 109-116

Author(s):

Xing Liu ◽

Jia Fu ◽

Man Man Han ◽

Kai Xin Sun ◽

Sheng Li Wei

Keyword(s):

Electronic Structure ◽

Debye Temperature ◽

First Principles ◽

Density Functional ◽

Elastic Moduli ◽

Poisson Ratio ◽

Structural Parameters ◽

Functional Material ◽

Covalent Bonds ◽

Functional Theory

As a potential functional material in the perovskite family, the KCaF3 on electronic structure, elasticity, Debye temperature and anisotropy are studied based on density functional theory (DFT). Above all, the structural parameters of KCaF3 crystal are optimized. Then the elastic constants and Debye temperature are calculated. The results show that: (1) KCaF3 is composed of covalent bonds, in which the Ca-F bond is stronger than K-F. (2) Ca atom mainly contributes for the electronic properties of KCaF3. (3) The structural parameters of KCaF3 is in fair agreement with the experimental data. (4) The anisotropy of KCaF3 was analyzed from the pure and quasi waves, of which the longitudinal wave velocity in the direction of [100] is the larger than the others two directions ([110] and [111]). Finally, The homogenized elastic moduli (bulk modulus B, shear modulus G, Young's modulus E), Pugh and Poisson ratio, are obtained. This research is meaningful and thus to provides a good theoretical guidance for the design the new ABX3-type material with better performance.

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First-principles investigation of MoS2 monolayer adsorbed on SiO2 (0001) Surface

Modern Physics Letters B ◽

10.1142/s0217984917502293 ◽

2017 ◽

Vol 31 (25) ◽

pp. 1750229 ◽

Cited By ~ 5

Author(s):

Xiangying Su ◽

Hongling Cui ◽

Weiwei Ju ◽

Yongliang Yong ◽

Xiaohong Li

Keyword(s):

Density Functional Theory ◽

Electronic Structure ◽

Charge Transfer ◽

First Principles ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Interlayer Spacing ◽

Covalent Bonds ◽

Functional Theory ◽

Mos2 Monolayer

In this paper, the geometric and electronic structure of MoS2 monolayer (ML) adsorbed on SiO2 (0001) surface were studied by using density functional theory calculations. The calculated interfacial binding energy shows that the MoS2/SiO2 hybrid system is stable. MoS2 ML is bound to the SiO2 surface with a big interlayer spacing and no covalent bonds form at the interface. The study of the density of states and the charge transfer indicates that the interaction between MoS2 ML and the SiO2 substrate is very weak. As a result, the electronic properties of MoS2 ML are almost not affected by the SiO2 substrate. This work will be beneficial to the design of MoS2 ML-based devices where a substrate is needed.

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