Structural, Electronic and Optical Properties of High (γ)-Li2BeSiO4: First-Principles Calculations

We have performed ab-initio total energy calculations using the plane-wave ultrasoft pseudopotential technique based on the first-principles density-functional theory (DFT) to study structural parameters, electronic structure, chemical bonding and optical properties of orthorhombic Li2BeSiO4. The calculated lattice parameters are in agreement with experimental data. The band structure shows a direct band gap. From the DOS analysis, charge densities and population analysis, electronic and chemical bonding properties have been studied. Furthermore, in order to understand the mechanism of optical transitions of orthorhombic Li2BeSiO4, the complex dielectric functions are calculated and analysed.

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First-Principles Study of Electronic Structure and Optical Properties of Tetragonal PbMoO4

ISRN Condensed Matter Physics ◽

10.5402/2011/290741 ◽

2011 ◽

Vol 2011 ◽

pp. 1-7

Author(s):

Qi-Jun Liu ◽

Zheng-Tang Liu ◽

Li-Ping Feng ◽

Hao Tian

Keyword(s):

Optical Properties ◽

Chemical Bonding ◽

First Principles ◽

Density Functional ◽

Structural Parameters ◽

Functional Theory ◽

Conductivity Function ◽

Structure Density ◽

Indirect Band Gap ◽

Electronic Chemical

Using the plane-wave ultrasoft pseudopotential technique based on the first-principles density functional theory (DFT), we have studied the structural, electronic, chemical bonding, and optical properties of tetragonal PbMoO4. The obtained structural parameters are in good agreement with experiments. Band structure, density of states, and chemical bonding are calculated and shown. It is found that tetragonal PbMoO4 is an indirect band gap. The dielectric function, refractive index, extinction coefficient, reflectivity, absorption coefficient, loss function, and conductivity function are calculated for radiation up to 20 eV.

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First-principles calculations of the structural, elastic, mechanical, electronic and optical properties of monoclinic Hf4CuSi4

International Journal of Modern Physics B ◽

10.1142/s0217979220500356 ◽

2020 ◽

Vol 34 (06) ◽

pp. 2050035

Author(s):

Xia Xu ◽

Wei Zeng ◽

Fu-Sheng Liu ◽

Zheng-Tang Liu ◽

Qi-Jun Liu

Keyword(s):

Optical Properties ◽

Band Structure ◽

First Principles ◽

Density Functional ◽

Mechanical Stability ◽

Elastic Anisotropy ◽

Structural Parameters ◽

Functional Theory ◽

Text Structures ◽

Structure Density

In this paper, the structural, electronic, elastic, mechanical and optical properties of monoclinic [Formula: see text] are studied using the first-principles density functional theory (DFT). The calculated structural parameters are consistent with the experimental data. The elastic constants of [Formula: see text] structures are calculated, indicating that [Formula: see text] shows mechanical stability and elastic anisotropy. According to the [Formula: see text] and Poisson’s ratio, monoclinic [Formula: see text] shows a brittle manner. The energy band structure, density of states, charge transfers and bond populations are given. And the band structure shows that the material is a metal conductor. Moreover, the optical properties and optical anisotropy of [Formula: see text] are shown and analyzed.

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Effects of Si Doping on the Structural, Electronic and Optical Properties of Barium Chalcogenide BaS: A First-Principles Study

SPIN ◽

10.1142/s2010324720500149 ◽

2020 ◽

Vol 10 (02) ◽

pp. 2050014

Author(s):

H. Absike ◽

H. Labrim ◽

B. Hartiti ◽

H. Ez-Zahraouy

Keyword(s):

Optical Properties ◽

First Principles ◽

Density Functional ◽

Original Structure ◽

Functional Theory ◽

Electron Charge Density ◽

Electronic And Optical Properties ◽

Charge Densities ◽

The Density Functional Theory ◽

Si Doped

In this work, the structural, electronic and optical properties of Si-doped barium chalcogenide [barium sulfide (BaS)] with different Si concentrations ([Formula: see text]) are investigated by the first-principles calculations based on the density functional theory (DFT). The band structures, charge densities and complex dielectric functions of the pure as well as Si-doped BaS were presented and analyzed in detail using TB-mBJ approach by WIEN2k package. It is found that silicon concentration can control the bandgap by reducing it to values around 1.4[Formula: see text]eV and 1.6[Formula: see text]eV for 12.5% and 6.25% of Si-doped BaS, respectively. The electron charge density indicates the ionic bonding between silicon and sulfur atoms due to the high electronegativity between them. In fact, the results show that the absorption peaks of Si-doped BaS are enhanced compared with pure BaS. These results suggest that the Ba[Formula: see text]SixS original structure displays excellent physical properties thereby revealing that it is a promising material in advanced optoelectronic and solar cell applications.

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STRUCTURAL PARAMETERS AND OPTOELECTRONIC PROPERTIES OF Mg-IV-V2 (IV=Si, Ge, Sn AND V=P, As) COMPOUNDS

Surface Review and Letters ◽

10.1142/s0218625x18501081 ◽

2018 ◽

Vol 25 (05) ◽

pp. 1850108 ◽

Cited By ~ 1

Author(s):

M. IBRAHIM ◽

HAYAT ULLAH ◽

SAEED ULLAH JAN ◽

MANZAR ALI ◽

M. GULBAHAR ASHIQ

Keyword(s):

Optical Properties ◽

Band Gap ◽

Density Functional ◽

Structural Parameters ◽

Visible Region ◽

Functional Theory ◽

Lattice Constants ◽

Direct Band Gap ◽

Semiconductor Behavior ◽

Direct Band

Semiconductors are the backbone of the optoelectronic industry. Direct band gap materials in the visible energy region are highly desirable for the efficient optoelectronic applications. In this work, we have probed the structural, electronic and optical properties of Mg-IV-V2 (IV[Formula: see text]Si, Ge, Sn and V[Formula: see text]P, As) compounds by FP-LAPW calculations, based on density functional theory. Their crystal structure is chalcopyrite with space group of I-42d. The lattice constants of MgSiP2, MgSiAs2 and MgGeAs2 are consistent with experimental results. These compounds show semiconductor behavior with direct band gap ranging from 1.3–2.15[Formula: see text]eV. Optical properties were also investigated. Optical properties include real and imaginary parts of dielectric constant, energy loss function, refraction and reflection. Direct band gap nature and good response in the visible region of these compounds predict their usefulness in optoelectronic devices.

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First-Principles Calculations on Structural, Electronic, and Optical Properties of 2H-CuAlO2

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.197-198.487 ◽

2011 ◽

Vol 197-198 ◽

pp. 487-490 ◽

Cited By ~ 1

Author(s):

Li Ping Feng ◽

Zheng Tang Liu ◽

Qi Jun Liu

Keyword(s):

Refractive Index ◽

Optical Properties ◽

Band Structure ◽

First Principles ◽

Density Functional ◽

Lattice Parameters ◽

Functional Theory ◽

Electronic And Optical Properties ◽

Charge Densities ◽

Densities Of States

Structural, electronic and optical properties of 2H-CuAlO2 were computed, using the plane-wave ultrasoft pseudopotential technique based on the first-principles density functional theory (DFT). The equilibrium lattice parameters, band structure, densities of states (DOS) and charge densities of 2H-CuAlO2 have been obtained. The equilibrium lattice parameters, band structure and DOS are found to be in good agreement with the available experimental and calculational values. The charge densities and the chemical bonding of 2H-CuAlO2 are analyzed, which show that bonding between Cu and O is mainly covalent due to Cu 3d and O 2p hybridization and that bonding between Al and O is mainly ionic. The complex dielectric function, refractive index and absorption coefficient of 2H-CuAlO2 have been predicted. The calculated static dielectric constant and static refractive index of 2H-CuAlO2 is 7.1 and 2.66, respectively.

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First-principles calculations to investigate structural, electronic and optical properties of (AlSb)m/(GaSb)n superlattices

Materials Science-Poland ◽

10.2478/msp-2020-0027 ◽

2020 ◽

Vol 38 (2) ◽

pp. 320-327

Author(s):

M. Caid ◽

D. Rached

Keyword(s):

Optical Properties ◽

First Principles ◽

Density Functional ◽

Local Density ◽

Orbital Method ◽

Full Potential ◽

Functional Theory ◽

Electronic And Optical Properties ◽

The Density Functional Theory ◽

Direct Band

AbstractThe structural, electronic and optical properties of (AlSb)m/(GaSb)n (m-n: 1-1, 2-2, 1-3 and 3-1) superlattices are investigated within the density functional theory (DFT) by using the last version of the first principles full potential linear muffin tin orbital method (FP-LMTO) as implemented in LmtART 7.0 code. The exchange and correlation potential is treated by the local density approximation (LDA) for the total energy calculations. Our calculations of the band structure show that the superlattices (n ≠ 1) have a direct band gap Γ-Γ. The optical constants, including the dielectric function ϵ(w), the refractive index n(w) and the reflectivity R(w) are calculated and discussed.

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Exo⇔Endo Isomerism, MEP/DFT, XRD/HSA-Interactions of 2,5-Dimethoxybenzaldehyde: Thermal, 1BNA-Docking, Optical, and TD-DFT Studies

Molecules ◽

10.3390/molecules25245970 ◽

2020 ◽

Vol 25 (24) ◽

pp. 5970

Author(s):

Nabil Al-Zaqri ◽

Mohammed Suleiman ◽

Anas Al-Ali ◽

Khaled Alkanad ◽

Karthik Kumara ◽

...

Keyword(s):

Density Functional ◽

Energy Gap ◽

Structural Parameters ◽

Population Analysis ◽

Xrd Analysis ◽

X Ray Diffraction ◽

Optical Energy Gap ◽

Functional Theory ◽

Reactivity Descriptors ◽

Td Dft

The exo⇔endo isomerization of 2,5-dimethoxybenzaldehyde was theoretically studied by density functional theory (DFT) to examine its favored conformers via sp2–sp2 single rotation. Both isomers were docked against 1BNA DNA to elucidate their binding ability, and the DFT-computed structural parameters results were matched with the X-ray diffraction (XRD) crystallographic parameters. XRD analysis showed that the exo-isomer was structurally favored and was also considered as the kinetically preferred isomer, while several hydrogen-bonding interactions detected in the crystal lattice by XRD were in good agreement with the Hirshfeld surface analysis calculations. The molecular electrostatic potential, Mulliken and natural population analysis charges, frontier molecular orbitals (HOMO/LUMO), and global reactivity descriptors quantum parameters were also determined at the B3LYP/6-311G(d,p) level of theory. The computed electronic calculations, i.e., TD-SCF/DFT, B3LYP-IR, NMR-DB, and GIAO-NMR, were compared to the experimental UV–Vis., optical energy gap, FTIR, and 1H-NMR, respectively. The thermal behavior of 2,5-dimethoxybenzaldehyde was also evaluated in an open atmosphere by a thermogravimetric–derivative thermogravimetric analysis, indicating its stability up to 95 °C.

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First-principles investigation of the electronic band structures and optical properties of quaternary ABaMQ4 (A = Rb, Cs; M = P, V; and Q = S) metal chalcogenides

International Journal of Modern Physics B ◽

10.1142/s021797921850337x ◽

2018 ◽

Vol 32 (30) ◽

pp. 1850337

Author(s):

Shahid Ullah ◽

Hayat Ullah ◽

Abdullah Yar ◽

Sikander Azam ◽

A. Laref

Keyword(s):

Optical Properties ◽

First Principles ◽

Density Functional ◽

Correlation Energy ◽

Electronic Charge ◽

Electromagnetic Spectrum ◽

Metal Chalcogenides ◽

Electronic Band ◽

Charge Densities ◽

Electronic Band Structures

In this paper, we study the optoelectronic properties of quaternary metal chalcogenide semiconductor ABaMQ4 (A = Rb, Cs; M = P, V; and Q = S) compounds using state-of-the-art density functional theory (DFT) with TB-mBJ approximation for the treatment of exchange-correlation energy. In particular, the electronic and optical properties of the relaxed geometries of these compounds are investigated. Our first-principles ab-initio calculations show that the CsBaPS4 and RbBaPS4 compounds have direct bandgaps whereas the CsBaVS4 compound exhibits indirect bandgap nature. Importantly, the theoretically calculated values of the bandgaps of the compounds are consistent with experiment. Furthermore, our analysis of the electronic charge densities of these compounds indicates that the above quaternary chalcogenides have mixed covalent and ionic bonding characters. The effective masses of these compounds are also calculated which provide very useful information about the band structure and transport characteristics of the investigated compounds. Similarly, high absorptivity in the visible and ultraviolet regions of the electromagnetic spectrum possibly predicts and indicates the importance of these materials for potential optoelectronic applications in this range.

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First principles study of structure, electronic and optical properties of Y3Fe5O12 in cubic and trigonal phases

Materials Science-Poland ◽

10.1515/msp-2015-0015 ◽

2015 ◽

Vol 33 (1) ◽

pp. 169-174 ◽

Cited By ~ 4

Author(s):

Shen Tao ◽

Hu Chao ◽

Dai Hailong ◽

Yang Wenlong ◽

Liu Hongchen ◽

...

Keyword(s):

Refractive Index ◽

Optical Properties ◽

Energy Loss ◽

First Principles ◽

Structural Parameters ◽

Band Gaps ◽

First Principles Calculations ◽

Electronic And Optical Properties ◽

Direct Band ◽

Experimental Values

AbstractFirst principles calculations have been performed to investigate the structure, electronic and optical properties of Y3Fe5O12. Both the cubic and trigonal phases have been considered in our calculation. The calculated structural parameters are slightly larger than the experimental values. The band structures show that Y3Fe5O12 in cubic and trigonal phases have direct band gaps of 0.65 and 0.17 eV. The calculations of dielectric function, absorption, extinction coefficient, refractive index, energy loss function and reflectivity are presented.

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The adsorption of nitrogen oxides on noble metal-doped graphene: The first-principles study

Modern Physics Letters B ◽

10.1142/s0217984919500441 ◽

2019 ◽

Vol 33 (04) ◽

pp. 1950044 ◽

Cited By ~ 2

Author(s):

X. Jia ◽

L. An

Keyword(s):

Gas Sensors ◽

First Principles ◽

Density Functional ◽

Noble Metals ◽

Functional Theory ◽

Adsorption Effect ◽

Charge Densities ◽

Adsorption Of Nitrogen ◽

Doped Graphene ◽

Metal Doped

The first-principles method based on density functional theory has been used to investigate the adsorption performance of NO/NO2 molecules on intrinsic, Ag-doped, Pt-doped and Au-doped graphene. Results show that graphene doped with Ag/Pt/Au has shorter final adsorption distance, larger adsorption energy and charge transfer amount with NO/NO2 molecules than intrinsic graphene, and the charge densities of doped graphene and NO/NO2 molecules overlap effectively. Therefore, doping graphene with noble metals can greatly enhance the adsorption between graphene and NO/NO2 molecules. Analysis also reveals that Au-doped graphene has the strongest adsorption effect on NO/NO2 molecules, followed by Ag-doped graphene, while Pt-doped graphene has the weakest role on the adsorption of NO/NO2 molecules. The work conducted in this research provides a theoretical guidance for the application of NO/NO2 gas sensors based on graphene.

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