The elastic, electronic and optical properties of RbCaX3 (X = F, Cl) compounds

The structural, elastic, chemical bonding, electronic and optical properties of the cubic perovskites RbCaX 3 ( X = F , Cl ) compounds are obtained by the full-potential linear augmented plane wave (FP-LAPW) method based on the density functional theory. The calculated lattice constants and bulk moduli within GGA agree with previous calculations. It is found that the bulk modulus decreases as the lattice constant increases when traversing from F to Cl in RbCaX 3. Both compounds are found to be elastically stable and anisotropy from the analysis of elastic constants. The analysis of Poisson's ratio, Cauchy pressure and Pugh's index ratio indicate that the RbCaF 3 is brittle compound while the RbCaCl 3 is ductile compound. The Debye temperature for the RbCaX 3 compound evaluates from the average sound velocity. Both compounds are found to have the indirect band-gap ( M -Γ) from calculating the band structure. The bonding nature of RbCaX 3 compounds is ionic with a minute covalent bonding. The optical properties are calculated for radiation up to 30 eV. The main peaks of the optical spectra are discussed in terms of the calculated electronic structure. A beneficial optoelectronic and optics technology is predicted from optical spectra.

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Prediction of electronic and optical properties for Zn1-xCdxSeyTe1-y quaternary alloys: First-principles study

Revista Mexicana de Física ◽

10.31349/revmexfis.67.041001 ◽

2021 ◽

Vol 67 (4 Jul-Aug) ◽

pp. 041001

Author(s):

K. Benchikh ◽

M. Benchehima ◽

H. A. Bid ◽

A. Chabane Chaouche

Keyword(s):

Optical Properties ◽

Density Functional ◽

Energy Gap ◽

Local Density ◽

Quaternary Alloy ◽

Full Potential ◽

Generalized Gradient ◽

Quaternary Alloys ◽

Electronic And Optical Properties ◽

The Density Functional Theory

In the present work, the density functional theory (DFT) was performed for the investigation of the structural, electronic and optical properties of the Zn1-xCdxSeyTe1-y quaternary alloys using the full potential linearized augmented plane wave (FP-LAPW) method. For the calculations of the structural properties we have used the Perdew-Burke-Ernzerhof generalized gradient approximation (GGA-PBEsol). On other hand, the electronic properties have been computed within the local density approximation (LDA) in adding to the Tran-Blaha modified Becker-Johnson (TB-mBJ) approach. Our results indicate that the lattice constant, as well as the bulk modulus and the energy gap for the Zn1-xCdxSeyTe1-y quaternary show almost linear variations on the concentration x (0.125≤x≤0.875). In addition, the simulated band structures for theZn1-xCdxSeyTe1-y quaternary exhibits a direct-gap for all concentrations. Moreover, low bowing parameters are observed. Also, some interesting optical properties such as dielectric constant, refractive index, extinction coefficient, absorption coefficient and reflectivity have been calculated by using the TB-mBJ method. The results of our computations shows that theZn1-xCdxSeyTe1-y quaternary alloy is a promissing candidate for optoelectronic applications. It is noteworthy that the present work is the first theoretical study of the quaternary of interest using the FP-LAPW calculations.

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Theoretical studies on the structural, electronic and optical properties of BeZnO alloys

Materials Science-Poland ◽

10.2478/msp-2020-0072 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

D.P. Xiong ◽

S.L. Zhou ◽

M. He ◽

Q. Wang ◽

W. Zhang ◽

...

Keyword(s):

Optical Properties ◽

Density Functional ◽

Functional Theory ◽

Electronic And Optical Properties ◽

Lattice Constants ◽

Maximum Value ◽

Formation Enthalpies ◽

The Density Functional Theory ◽

Hubbard U ◽

Theoretical Results

Abstract The structural, electronic and optical properties of BexZn1−xO alloys were studied using the density functional theory and Hubbard-U method. Uo;p = 10.2 eV for O 2p and UZn;d = 1.4 eV for Zn 3d were adopted as the Hubbard U values. For BexZn1−x O alloys, the lattice constants a and c decrease linearly as Be concentration increases, the bandgap increases with a large bowing parameter of 6.95 eV, the formation enthalpies have the maximum value with Be concentration at 0.625, corresponding to the possible Be concentration to form phase separation. These calculations comply well with the experimental and other theoretical results. Furthermore, optical properties, such as dielectric function ∈(ω), reflectivity R(ω), absorption coefficient α(ω), were calculated and discussed for BexZn1−x O alloys with the incident photon energy ranging from 0 eV to 30 eV.

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Theoretical Calculations of Structural, Mechanical, Electronic And Optical Properties of Sn2S3 Under Pressure

10.21203/rs.3.rs-789940/v1 ◽

2021 ◽

Author(s):

Baishu Chen ◽

Wenxia Zhu ◽

Chunxiang Wang ◽

Chang Wang ◽

Yuanzuo Li ◽

...

Keyword(s):

Optical Properties ◽

Band Gap ◽

Density Functional ◽

Mechanical Stability ◽

Pressure Effect ◽

Theoretical Calculations ◽

Structural Parameters ◽

Electronic And Optical Properties ◽

Lattice Constants ◽

The Density Functional Theory

Abstract The pressure effect on the structural, mechanical, electronic and optical properties of Sn2S3 in the pressure range of 0–35 GPa have been evaluated by means of the first-principles calculations based on the density-functional theory. The structural parameters of Sn2S3 at 0 GPa such as lattice constants and cell volumes are consistent with the previous theoretical and experiment reports. The mechanical properties about the elastic constants (Cij) and polycrystalline elastic modulus (B, G and E) under pressure are calculated for the first time. Furthermore, the results suggest that the Sn2S3 is predicted to be mechanically stable in the range of pressure from 0 to 35 GPa in the light of the mechanical stability conditions. The Sn2S3 is found to be ductile from the value of B/G. With the increasing of pressure, the ductility of Sn2S3 enhances monotonously. The pressure effect on the energy band gap and density of states of Sn2S3 is also discussed, which indicates that the pressure makes the band gap of Sn2S3 decreased. The optical properties of Sn2S3 are calculated in the range 0–35 eV, and the results show that the Sn2S3 under pressure has stronger visible light absorption in comparison with 0 GPa.

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The Influence of Oxygen Substitution on the Optoelectronic Properties of ZnTe

Journal of Chemistry ◽

10.1155/2016/8160169 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Imad Khan ◽

Sajid Khan ◽

Javid Iqbal ◽

H. A. Rahnamaye Aliabad ◽

Zahid Ali ◽

...

Keyword(s):

Optical Properties ◽

Density Functional ◽

Plane Waves ◽

Full Potential ◽

Functional Theory ◽

Electronic And Optical Properties ◽

Lattice Constants ◽

Linear Behavior ◽

Oxygen Substitution ◽

Theoretical Results

We communicate theoretical results of the structural, electronic, and optical properties ofZnOxTe1-x(0≤x≤1) in the zincblende structure. The calculations are performed using full potential linearized augmented plane waves (FP-LAPW) method, based on density functional theory (DFT). The structural properties are calculated with simple GGA (PBEsol), while the electronic and optical properties are calculated using mBJ-GGA. The mBJ-GGA is used to properly treat the active d-orbital in their valence shell. The ZnOTe alloy is highly lattice mismatched and consequently the lattice constants and bulk moduli largely deviate from the linear behavior. The calculated bandgaps are in agreement with the experimentally measured values, where the nature of bandgaps is direct for the whole range ofxexcept atx=0.25. We also calculate the bandgap bowing parameter from our accurate bandgaps and resolve the existing controversy in this parameter.

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The Electronic and Optical Properties of InSe-GeTe Heterobilayer via Applying Biaxial Strain

Nanomaterials ◽

10.3390/nano9121705 ◽

2019 ◽

Vol 9 (12) ◽

pp. 1705 ◽

Cited By ~ 1

Author(s):

Guofeng Yang ◽

Rui Sun ◽

Yan Gu ◽

Feng Xie ◽

Yu Ding ◽

...

Keyword(s):

Optical Properties ◽

Density Functional ◽

Band Alignment ◽

The Novel ◽

Biaxial Strain ◽

Functional Theory ◽

Electronic And Optical Properties ◽

The Density Functional Theory ◽

Small Lattice ◽

Indirect Band Gap

A comprehensive insight into the electronic and optical properties of small-lattice-mismatched InSe-GeTe heterobilayer (HBL) is performed based on the density functional theory (DFT) with van der Waals corrections from first-principles perspective. The optimization of most stable geometric stacking mode for the InSe-GeTe HBL is demonstrated. In addition, it is found that the InSe-GeTe HBL forms a type-II heterostructure of staggered-gap band alignment, resulting in an indirect band gap of 0.78 eV, which could be employed as a separator for electron-hole pairs. Moreover, the influence of biaxial strain on the electronic and optical properties of the InSe-GeTe HBL are systematically explored by calculating the band structures, density of states (PDOS), electron density differences, and optical absorption spectra of InSe-GeTe HBL under compressive and tensile biaxial strains. The results indicate that the electronic structures and optical performance of InSe-GeTe HBL could be modulated by changing the biaxial strain conveniently. Our findings provide new opportunities for the novel InSe-GeTe HBL to be applied in the electronic and optoelectronic fields.

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Theoretical investigations of the structural, electronic and optical properties of Hg1−xCdxS alloys

Modern Physics Letters B ◽

10.1142/s0217984916501736 ◽

2016 ◽

Vol 30 (11) ◽

pp. 1650173 ◽

Cited By ~ 3

Author(s):

S. Al-Rajoub ◽

B. Hamad

Keyword(s):

Optical Properties ◽

Density Functional ◽

Local Density ◽

Ternary Alloys ◽

Full Potential ◽

Generalized Gradient ◽

Metallic Behavior ◽

Electronic And Optical Properties ◽

Lattice Constants ◽

Theoretical Investigations

The structural, electronic and optical properties of mercury cadmium sulfide (Hg[Formula: see text]Cd[Formula: see text]S) alloys with [Formula: see text] = 0.0, 0.25, 0.5, 0.75 are studied using density functional theory (DFT) within full-potential linearized augmented plane wave (FPLAPW) method. We used the local density approximation (LDA), the generalized gradient approximation (GGA), Hubbard-corrected functionals (GGA/LDA[Formula: see text]+[Formula: see text][Formula: see text]) and the modified Becke–Johnson (LDA/GGA)-mjb hybrid potentials to treat the exchange-correlation functional [Formula: see text]. We found that LDA functional predicts better lattice constants than GGA functional. Mercury sulfide (HgS) binary alloy was found to exhibit a semi-metallic behavior using all functional with an inverted band gap close to the experimental value. However, the hybrid functionals were more successful than LDA and GGA functionals to predict the correct electronic structure of Hg[Formula: see text]Cd[Formula: see text]S ternary alloys. The results of the electronic and optical band gaps are consistent for Hg[Formula: see text]Cd[Formula: see text]S ternary alloys.

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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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First principles calculation of structural, electronic and optical properties of (001) and (110) growth axis (InN)/(GaN)n superlattices

Revista Mexicana de Física ◽

10.31349/revmexfis.67.7 ◽

2021 ◽

Vol 67 (1 Jan-Feb) ◽

pp. 7

Author(s):

B. Bachir Bouiadjra ◽

N. Mehnane ◽

N. Oukli

Keyword(s):

Optical Properties ◽

Density Functional ◽

Electronic Band Structure ◽

Scale Up ◽

Energy Scale ◽

First Principles Calculation ◽

Full Potential ◽

Electronic Band ◽

Electronic And Optical Properties ◽

Growth Axis

Based on the full potential linear muffin-tin orbitals (FPLMTO) calculation within density functional theory, we systematically investigate the electronic and optical properties of (100) and (110)-oriented (InN)/(GaN)n zinc-blende superlattice with one InN monolayer and with different numbers of GaN monolayers. Specifically, the electronic band structure calculations and their related features, like the absorption coefficient and refractive index of these systems are computed over a wide photon energy scale up to 20 eV. The effect of periodicity layer numbers n on the band gaps and the optical activity of (InN)/(GaN)n SLs in the both growth axis (001) and (110) are examined and compared. Because of prospective optical aspects of (InN)/(GaN)n such as light-emitting applications, this theoretical study can help the experimental measurements.

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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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Electronic and optical properties of zinc-blende GeC by first principles study

Modern Physics Letters B ◽

10.1142/s0217984915501031 ◽

2015 ◽

Vol 29 (20) ◽

pp. 1550103

Author(s):

Jinhui Zhai ◽

Jinguang Zhai ◽

Ajun Wan

Keyword(s):

Optical Properties ◽

First Principles ◽

Density Functional ◽

Dielectric Constants ◽

Electronic And Optical Properties ◽

Optical Functions ◽

Zinc Blende ◽

The Density Functional Theory ◽

Valence Bands ◽

Energy Dependent

The electronic and optical properties of zinc-blende (zb)[Formula: see text]GeC have been investigated using first principles calculations based on the density functional theory (DFT). The obtained band gap of zb–GeC is 2.30[Formula: see text]eV by means of Heyd–Scuseria–Ernzerhof (HSE) functional. We have discussed the energy-dependent optical functions including dielectric constants, refractive index, absorption, reflectivity, and energy-loss spectrum in detail. The results reveal that zb–GeC has a higher static dielectric constant compared with that of zb–SiC. The optical functions are mainly associated with the interband transitions from the occupied valence bands (VBs) Ge[Formula: see text][Formula: see text] and C[Formula: see text][Formula: see text] states to Ge[Formula: see text][Formula: see text], [Formula: see text] and C[Formula: see text][Formula: see text] states of the unoccupied conduction bands (CBs).

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