Magnetic and optical properties in the 1D TM–O chain compounds Sr2TMO3 (TM = Ni, Co): A first-principle investigation

In this paper, we have calculated the structural, electronic, magnetic and optical properties of Sr2NiO3 and Sr2CoO3 using density functional theory (DFT) within generalized gradient approximation (GGA). The crystal structure of both materials is well described with Immm (No. 71) symmetry which are isostructural with Sr2CuO3 and both are quasi-one-dimensional (1D) rectangular lattice G-type antiferromagnets, in consistent with the experimental data. Due to a distortion, Sr2CoO3 lifts the near-degeneracy [Formula: see text] and [Formula: see text] states of the local Co electronic configuration, which demonstrates a strong coupling between the structural lattice and the electronic configuration. The calculated band structure shows a band gap of 1.376 eV for Sr2NiO3 and a band gap of 1.735 eV for Sr2CoO3. Ni and Co ions are in the high-spin [Formula: see text] and [Formula: see text] configurations with the magnetic moments of 1.585 [Formula: see text] and 2.587 [Formula: see text], respectively. Based on the Heisenberg Hamiltonian model, we conclude that the superexchange intrachain TM–O–TM superexchange interaction is predominant and interaction between the 1D chains is weak. According to the calculated dielectric function, absorption spectrum and electron energy loss spectrum, the optical responses suggest that Sr2NiO3 shows the unique anisotropic structure and interaction of the application in optoelectronics.

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Structural Electronic and Optical Properties of MgO, CaO and SrO Binary Compounds: Comparison Study

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.257.123 ◽

2016 ◽

Vol 257 ◽

pp. 123-126 ◽

Cited By ~ 3

Author(s):

Salima Labidi ◽

Jazia Zeroual ◽

Malika Labidi ◽

Kalthoum Klaa ◽

Rachid Bensalem

Keyword(s):

Optical Properties ◽

Band Gap ◽

Density Functional ◽

Local Density ◽

Alternative Form ◽

Full Potential ◽

Generalized Gradient ◽

Electronic And Optical Properties ◽

Optical Dielectric Constant ◽

Reported Data

First-principles calculations for electronic and optical properties under pressure effect of MgO, SrO and CaO compounds in the cubic structure, using a full relativistic version of the full-potential augmented plane-wave (FP-LAPW) method based on density functional theory, within the local density approximation (LDA) and the generalized gradient approximation (GGA), have been reported. Furthermore, band structure calculations have been investigated by the alternative form of GGA proposed by Engel and Vosko (GGA-EV) and modified by Becke-Johnson exchange correlation potential (MBJ-GGA). All calculated equilibrium lattices, bulk modulus and band gap at zero pressure are find in good agreement with the available reported data. The pressure dependence of band gap and the static optical dielectric constant are also investigated in this work.

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Crystal Structure and Photoelectric Property of Thin-Film Solar Cell Materials Cd1-xZnxS

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.512-515.23 ◽

2012 ◽

Vol 512-515 ◽

pp. 23-29

Author(s):

Fu Cheng Wan ◽

Wen Jiang Lu ◽

Fu Ling Tang ◽

Yu Dong Feng ◽

Zhi Min Wang ◽

...

Keyword(s):

Crystal Structure ◽

Optical Properties ◽

Electrical Properties ◽

Absorption Coefficient ◽

Band Gap ◽

Density Functional ◽

Doping Concentration ◽

Optical Absorption Coefficient ◽

Generalized Gradient ◽

Rate Of Increase

Based on density functional theory (DFT) within the framework of the generalized gradient approximation method, we have studied the Cd1-xZnxS sphalerite crystal structure and optical properties. We calculated electronic and optical properties of Cd1-xZnxS at the doping concentration x = 0, 0.25, 0.50, 0.75, 1.0. Optical properties (reflectivity, absorption coefficient, refractive index, dielectric function) and the electrical properties (band structure, electron density, etc.) are obtained including Zn-doing effects on the crystal structure, optical properties and electrical properties. With the increase of doping concentration x, the lattice parameter reduces from 0.5910 nm to 0.5409 nm; as a direct wide band gap semiconductor, its band gap increased from 1.15 to 2.22. Optical absorption coefficient increases with the increase of doping concentration, but the rate of increase is relatively small.

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First-principles study of the structural, electronic, magnetic, elastic and optical properties of CoFeZrSi1−xGex(x = 0.00, 0.25, 0.50, 0.75, 1.00)

International Journal of Modern Physics B ◽

10.1142/s0217979219501583 ◽

2019 ◽

Vol 33 (15) ◽

pp. 1950158 ◽

Cited By ~ 1

Author(s):

Ramesh Paudel ◽

Jingchuan Zhu

Keyword(s):

Optical Properties ◽

Density Functional ◽

Magnetic Moments ◽

Theoretical Data ◽

Generalized Gradient ◽

Elastic Symmetry ◽

Metallic Behavior ◽

Lattice Constants ◽

Generalized Gradient Approximation ◽

First Time

The effect of germanium doping on the structural, magnetic, elastic and optical properties of the LiMgPdSn-type CoFeZrSi[Formula: see text]Ge[Formula: see text] alloys is predicted by utilizing ab initio density functional theory (DFT) with the generalized gradient approximation (GGA) and the electronic properties of the materials are investigated by using the generalized gradient approximation plus Hubbard coefficient (GGA + U). The estimated elevated lattice constant of CoFeZrGe compound agrees with existing theoretical data. The optimized lattice constants of CoFeZrSi[Formula: see text]Ge[Formula: see text](x = 0, 0.25, 0.50, 0.75) are 5.9022, 5.9631, 5.9752 and 5.9973 Å, respectively. These have been investigated for the very first time. The elastic symmetry (C[Formula: see text], C[Formula: see text], C[Formula: see text], C[Formula: see text], C[Formula: see text] and C[Formula: see text]), bulk modulus, shear modulus, Poisson’s ratio, anisotropy and Pugh ratio (B/G) are predicted and discussed. The calculation of band structure and density of states reveal that the materials considered have half-metallic behavior with 100% spin-polarization. The calculated magnetic moments of CoFeZrSi[Formula: see text]Ge[Formula: see text] are 0.99, 1.06, 1.02, 1.00 and 1.01 [Formula: see text], respectively, and agree with the SP rule, M[Formula: see text] = N[Formula: see text] − 24. The analysis of the elastic moduli indicates that the compounds are mechanically stable with a ductile nature. The CoFeZrSi[Formula: see text]Ge[Formula: see text] alloy is stiffer than the other compounds considered. Moreover, the dielectric functions, optical conductivity, reflectivity and absorption coefficient of CoFeZrSi[Formula: see text]Ge[Formula: see text] compounds are predicted by using complex dielectric functions.

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AB INITIO STUDY OF STRUCTURAL, ELECTRONIC AND OPTICAL PROPERTIES OF MgxCd1-xX (X = S, Se, Te) ALLOYS

International Journal of Modern Physics B ◽

10.1142/s0217979212501688 ◽

2012 ◽

Vol 26 (30) ◽

pp. 1250168 ◽

Cited By ~ 19

Author(s):

N. A. NOOR ◽

A. SHAUKAT

Keyword(s):

Optical Properties ◽

Band Gap ◽

Density Functional ◽

Theoretical Calculations ◽

Ternary Alloys ◽

Full Potential ◽

Generalized Gradient ◽

Calculated Density ◽

Electronic And Optical Properties ◽

Direct Band

This study describes structural, electronic and optical properties of Mg x Cd 1-x X (X = S, Se, Te) alloys in the complete range 0≤x ≤1 of composition x in the zinc-blende (ZB) phase with the help of full-potential linearized augmented plane wave plus local orbitals (FP-LAPW+lo) method within density functional theory (DFT). In order to calculate total energy, generalized gradient approximation (Wu–Cohen GGA) has been applied, which is based on optimization energy. For electronic structure calculations, the corresponding potential is being optimized by Engel–Vosko GGA formalism. Our calculations reveal the nonlinear variation of lattice constant and bulk modulus with different concentration for the end binary and their ternary alloys, which slightly deviates from Vegard's law. The calculated band structures show a direct band gap for all three alloys with increasing order in the complete range of the compositional parameter x. In addition, we have discussed the disorder parameter (gap bowing) and concluded that the total band gap bowing is substantially influenced by the chemical (electronegativity) contribution. The calculated density of states (DOS) of these alloys is discussed in terms of contribution from various s-, p- and d-states of the constituent atoms and charge density distributions plots are analyzed. Optical properties have been presented in the form of the complex dielectric function ε(ω), refractive index n(ω) and extinction coefficient k(ω) as function of the incident photon energy, and the results have been compared with existing experimental data and other theoretical calculations.

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First Principles Study of Electronic and Optical Properties of Pristine and X (Cu, Ag And Au) Doped BiOBr

Journal of Institute of Science and Technology ◽

10.3126/jist.v22i2.19595 ◽

2018 ◽

Vol 22 (2) ◽

pp. 63-69 ◽

Cited By ~ 1

Author(s):

Samir Paudel ◽

Puspa Raj Adhikari ◽

Om Prakash Upadhyay ◽

Gopi Chandra Kaphle ◽

Anurag Srivastava

Keyword(s):

Optical Properties ◽

Band Gap ◽

First Principles ◽

Electronic Structures ◽

Density Functional ◽

Generalized Gradient ◽

Functional Theory ◽

Ab Initio Approach ◽

Indirect Band Gap ◽

Standard Density

The electronic structures and optical properties of pristine BiOBr and Cu, Ag and Au doped BiOBr have been analyzed by using a standard density functional theory based ab-initio approach employing generalized gradient approximation through revised Perdew Burke Ernzerhoff type parameterization. The calculation shows that both the doped and pristine BiOBr have indirect band gap, the band gap of the pristine BiOBr found 2.22eV, whereas band gap significantly reduced after doping Cu, Ag and Au on BiOBr. The band gap of Cu, Ag and Au doped BiOBr are 1.2eV, 0.9eV and 1.76eV respectively. The optical properties have been studied through dielectric function, both pure and doped BiOBr shows anisotropic nature. Journal of Institute of Science and TechnologyVolume 22, Issue 2, January 2018, page: 63-69

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Ab initio calculation on the Optical Properties of AA- Stacked two dimensional Graphene, Silicene, Germanene, and Stanene

International Journal of Computational Physics Series ◽

10.29167/a1i1p46-50 ◽

2018 ◽

Vol 1 (1) ◽

pp. 46-50

Author(s):

Rita John ◽

Benita Merlin

Keyword(s):

Optical Properties ◽

Band Structure ◽

Density Functional ◽

Electronic Band Structure ◽

Complex Refractive Index ◽

Single Layer ◽

Generalized Gradient ◽

Electronic Band ◽

Wide Range ◽

Optical Region

In this study, we have analyzed the electronic band structure and optical properties of AA-stacked bilayer graphene and its 2D analogues and compared the results with single layers. The calculations have been done using Density Functional Theory with Generalized Gradient Approximation as exchange correlation potential as in CASTEP. The study on electronic band structure shows the splitting of valence and conduction bands. A band gap of 0.342eV in graphene and an infinitesimally small gap in other 2D materials are generated. Similar to a single layer, AA-stacked bilayer materials also exhibit excellent optical properties throughout the optical region from infrared to ultraviolet. Optical properties are studied along both parallel (||) and perpendicular ( ) polarization directions. The complex dielectric function (ε) and the complex refractive index (N) are calculated. The calculated values of ε and N enable us to analyze optical absorption, reflectivity, conductivity, and the electron loss function. Inferences from the study of optical properties are presented. In general the optical properties are found to be enhanced compared to its corresponding single layer. The further study brings out greater inferences towards their direct application in the optical industry through a wide range of the optical spectrum.

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Electronic and optical properties of vacancy ordered double perovskites A2BX6 (A = Rb, Cs; B = Sn, Pd, Pt; and X = Cl, Br, I): a first principles study

Scientific Reports ◽

10.1038/s41598-021-86145-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Muhammad Faizan ◽

K. C. Bhamu ◽

Ghulam Murtaza ◽

Xin He ◽

Neeraj Kulhari ◽

...

Keyword(s):

Optical Properties ◽

Band Gap ◽

First Principles ◽

Density Functional ◽

Perovskite Solar Cells ◽

Dielectric Constants ◽

Maximum Efficiency ◽

Exchange Potential ◽

Double Perovskites ◽

Electronic And Optical Properties

AbstractThe highly successful PBE functional and the modified Becke–Johnson exchange potential were used to calculate the structural, electronic, and optical properties of the vacancy-ordered double perovskites A2BX6 (A = Rb, Cs; B = Sn, Pd, Pt; X = Cl, Br, and I) using the density functional theory, a first principles approach. The convex hull approach was used to check the thermodynamic stability of the compounds. The calculated parameters (lattice constants, band gap, and bond lengths) are in tune with the available experimental and theoretical results. The compounds, Rb2PdBr6 and Cs2PtI6, exhibit band gaps within the optimal range of 0.9–1.6 eV, required for the single-junction photovoltaic applications. The photovoltaic efficiency of the studied materials was assessed using the spectroscopic-limited-maximum-efficiency (SLME) metric as well as the optical properties. The ideal band gap, high dielectric constants, and optimum light absorption of these perovskites make them suitable for high performance single and multi-junction perovskite solar cells.

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First principles calculations of structural, electronic and optical properties of InN compound

International Journal of Modern Physics B ◽

10.1142/s0217979215500289 ◽

2015 ◽

Vol 29 (05) ◽

pp. 1550028 ◽

Cited By ~ 4

Author(s):

R. Graine ◽

R. Chemam ◽

F. Z. Gasmi ◽

R. Nouri ◽

H. Meradji ◽

...

Keyword(s):

Optical Properties ◽

Band Structure ◽

Density Functional ◽

Local Density ◽

Indium Nitride ◽

Alternative Form ◽

Full Potential ◽

Generalized Gradient ◽

Pressure Derivative ◽

Electronic And Optical Properties

We carried out ab initio calculations of structural, electronic and optical properties of Indium nitride ( InN ) compound in both zinc blende and wurtzite phases, using the full-potential linearized augmented plane wave method (FP-LAPW), within the framework of density functional theory (DFT). For the exchange and correlation potential, local density approximation (LDA) and generalized gradient approximation (GGA) were used. Moreover, the alternative form of GGA proposed by Engel and Vosko (EV-GGA) and modified Becke–Johnson schemes (mBJ) were also applied for band structure calculations. Ground state properties such as lattice parameter, bulk modulus and its pressure derivative are calculated. Results obtained for band structure of these compounds have been compared with experimental results as well as other first principle computations. Our results show good agreement with the available data. The calculated band structure shows a direct band gap Γ → Γ. In the optical properties section, several optical quantities are investigated; in particular we have deduced the interband transitions from the imaginary part of the dielectric function.

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Oxygen vacancy and doping atom effect on electronic structure and optical properties of Cd2SnO4

RSC Advances ◽

10.1039/c7ra10641f ◽

2018 ◽

Vol 8 (2) ◽

pp. 640-646 ◽

Cited By ~ 8

Author(s):

Mei Tang ◽

JiaXiang Shang ◽

Yue Zhang

Keyword(s):

Optical Properties ◽

Electronic Structure ◽

Oxygen Vacancy ◽

Density Functional ◽

Generalized Gradient ◽

Functional Theory ◽

The Density Functional Theory ◽

La Doped ◽

Doping Atom ◽

Atom Effect

The electronic structure and optical properties of oxygen vacancy and La-doped Cd2SnO4 were calculated using the plane-wave-based pseudopotential method based on the density functional theory (DFT) within the generalized gradient approximation (GGA).

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Effect of Yb Concentration on the Structural, Magnetic and Optoelectronic Properties of Yb Doped ZnO: First Principles Calculation

10.21203/rs.3.rs-877060/v1 ◽

2021 ◽

Author(s):

Mohamed Achehboune ◽

Mohammed Khenfouch ◽

Issam Boukhoubza ◽

Issam Derkaoui ◽

Bakang Moses Mothudi ◽

...

Keyword(s):

Band Gap ◽

Conduction Band ◽

Density Functional ◽

Blue Shift ◽

First Principles Calculation ◽

Theoretical Research ◽

Generalized Gradient ◽

Functional Theory ◽

Doped Zno ◽

Good Agreement

Abstract Density functional theory-based investigation of the electronic, magnetic, and optical characteristics in pure and ytterbium (Yb) doped ZnO has been carried out by the plane-wave pseudopotential technique with generalized gradient approximation. The calculated lattice parameters and band gap of pure ZnO are in good agreement with the experimental results. The energy band-gap increases with the increase of Yb concentration. The Fermi level moves upward into the conduction band after doping with Yb, which shows the properties of an n-type se miconductor. New defects were created in the band-gap near the conduction band attributed to the Yb-4f states. The magnetic properties of ZnO were found to be affected by Yb doping; ferromagnetic property was observed for 4.17% Yb due to spin polarization of Yb-4f electrons. The calculated optical properties imply that Yb doped causes a blue shift of the absorption peaks, significantly enhances the absorption of the visible light, and the blue shift of the reflectivity spectrum was observed. Besides, a better transmittance of approximately 88% was observed for 4.17% Yb doped ZnO system. The refractive index and the extinction coefficient were observed to decrease as the Yb dopant concentration increased. As a result, we believe that our findings will be useful in understanding the doping impact in ZnO and will motivate further theoretical research.

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