Optical Properties of LaB6: A Computer Aided Simulation

2012 ◽  
Vol 571 ◽  
pp. 292-295
Author(s):  
Ben Hai Yu ◽  
Chao Xu ◽  
Dong Chen
Keyword(s):  
Optical Properties ◽  
Dielectric Function ◽  
Density Functional ◽  
Mechanical Stability ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Lattice Constants ◽  
The Density Functional Theory ◽  
Theoretical Results ◽  
Good Agreement

We report ab initio calculations of the structural, elastic and optical properties of the compound LaB6 as a function of pressure. The computation is based on the density functional theory in combination with the generalized gradient approximation functional. The calculated lattice constants and elastic moduli are compared with the theoretical results and a good agreement is found. LaB6 can retain its mechanical stability in the pressure range of 0-20GPa. Besides, the frequency-dependent dielectric function, absorption coefficient and loss function of LaB6 are also obtained. The calculated static dielectric function is 8.8 at 0GPa and 5GPa. The computed results should be testified by experiments.

scholarly journals Structural, Elastic, Electronic and Optical Properties of SrTMO3 (TM = Rh, Zr) Compounds: Insights from FP-LAPW Study

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2057 ◽  
Author(s):  
Areej Shawahni ◽  
Mohammed Abu-Jafar ◽  
Raed Jaradat ◽  
Tarik Ouahrani ◽  
Rabah Khenata ◽  
...  
Keyword(s):  
Optical Properties ◽  
Density Functional ◽  
Ultraviolet Region ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Electronic And Optical Properties ◽  
Lattice Constants ◽  
Far Ultraviolet ◽  
Theoretical Results ◽  
Good Agreement

The structural, mechanical, electronic and optical properties of SrTMO3 (TM = Rh, Zr) compounds are investigated by using first principle calculations based on density functional theory (DFT). The exchange-correlation potential was treated with the generalized gradient approximation (GGA) for the structural properties. Moreover, the modified Becke-Johnson (mBJ) approximation was also employed for the electronic properties. The calculated lattice constants are in good agreement with the available experimental and theoretical results. The elastic constants and their derived moduli reveal that SrRhO3 is ductile and SrZrO3 is brittle in nature. The band structure and the density of states calculations with mBJ-GGA predict a metallic nature for SrRhO3 and an insulating behavior for SrZrO3. The optical properties reveal that both SrRhO3 and SrZrO3 are suitable as wave reflectance compounds in the whole spectrum for SrRhO3 and in the far ultraviolet region (FUV) for SrZrO3.

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

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.

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

RSC Advances ◽  
2018 ◽  
Vol 8 (2) ◽  
pp. 640-646 ◽  
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).

scholarly journals DFT Calculation on the Electronic Structure and Optical Properties of InxGa1-xN Alloy Semiconductors

2019 ◽  
Vol 26 (2) ◽  
pp. 127-132
Author(s):  
Xuewen WANG ◽  
Wenwen LIU ◽  
Chunxue ZHAI ◽  
Jiangni YUN ◽  
Zhiyong ZHANG
Keyword(s):  
Optical Properties ◽  
Absorption Spectrum ◽  
Electronic Structure ◽  
Density Functional ◽  
Dft Calculation ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Photoelectric Performance ◽  
The Density Functional Theory ◽  
Alloy Semiconductors

Using the density functional theory (DFT) of the first principle and Generalized gradient approximation method, the electronic structures and optical properties of the InxGa1-xN crystals with different x (x = 0.25, 0.5, 0.75, 1) have been calculated in this paper. The influence of the electronic structure on the properties has been analyzed. Then the influence of doping quantity on the characteristics has been summarized, which also indicates the trend of complex dielectric function, absorption spectrum and transitivity. With the increase of x, the computational result shows that the optical band gap (i.e.Eg) of the InxGa1-xN crystal tends to be narrow, then the absorption spectrum shifts to the low-energy direction. And the Fermi energy slightly moves to the bottom of conduction band which would cause the growth of conductivity by increasing x. In a word, the InxGa1-xN compound can be achieved theoretically the adjustable Eg and photoelectric performance with x, which will be used in making various optoelectronic devices including solar cell and sensors.

Newly Determined Crystal Structure and Optical Property of the Intermetallic NiAl and Ni3Al Alloys: A First-Principles Computer Simulated Investigation

2014 ◽  
Vol 989-994 ◽  
pp. 220-223
Author(s):  
Chao Xu ◽  
Dong Chen
Keyword(s):  
Dielectric Function ◽  
Loss Function ◽  
First Principles ◽  
Density Functional ◽  
Peak Height ◽  
Functional Theory ◽  
Lattice Constants ◽  
Light Region ◽  
The Density Functional Theory ◽  
Lower Energy Region

Using quantum mechanics plane-wave approach based on the density functional theory, the lattice constants of NixAl at different Ni concentrations (x=1, 3) are predicted. Optical properties such as dielectric function, energy loss function and reflectivity are also investigated. Results show that with the increase of Ni constituent, the location of the peak in loss function moves to the lower energy region, but the peak height increases. At 0eV, the reflectivity increases rapidly with the Ni concentration. The reflectivity of NiAl and Ni3Al are pronounced in the UV region (not in the visible light region). The dielectric properties, namely the real and imaginary parts of the dielectric function, changed significantly with Ni constituent.

scholarly journals Pt(II) Complexes with Linear Diamines—Part I: Vibrational Study of Pt-Diaminopropane

2012 ◽  
Vol 27 ◽  
pp. 403-413 ◽  
Author(s):  
Ana L. M. Batista de Carvalho ◽  
Sónia M. Fiuza ◽  
John Tomkinson ◽  
Luís A. E. Batista de Carvalho ◽  
M. Paula M. Marques
Keyword(s):  
Density Functional ◽  
Spectroscopic Techniques ◽  
Functional Theory ◽  
Vibrational Study ◽  
Combined Use ◽  
The Density Functional Theory ◽  
Mechanical Methods ◽  
Reported Data ◽  
Theoretical Results ◽  
Good Agreement

A conformational analysis of the Pt(dap)Cl2complex (-diaminopropane) was performed by vibrational spectroscopy (FTIR, Raman, and INS), coupled to quantum mechanical methods within the density functional theory (DFT) and effective core potential (ECP) approaches. A complete spectral assignment of the system was achieved, due to the combined use of all available vibrational spectroscopic techniques. A good agreement was found between experimental and theoretical results, as well as with reported data for analogous complexes (e.g., cisplatin).

Electronic and optical properties of AlN under pressure: DFT calculations

2017 ◽  
Vol 31 (02) ◽  
pp. 1650255
Author(s):  
Sahar Javaheri ◽  
Arash Boochani ◽  
Manuchehr Babaeipour ◽  
Sirvan Naderi
Keyword(s):  
Optical Properties ◽  
Electronic Properties ◽  
Dielectric Function ◽  
First Principles ◽  
Density Functional ◽  
Functional Theory ◽  
Zinc Blende ◽  
Rocksalt Phase ◽  
Optical And Electronic Properties ◽  
Theoretical Results

Structural, elastic, optical, and electronic properties of wurtzite (WZ), zinc-blende (ZB), and rocksalt (RS) structures of AlN are investigated using the first-principles method and within the framework of density functional theory (DFT). Lattice parameters, bulk modulus, shear modulus, Young’s modulus, and elastic constants are calculated at zero pressure and compared with other experimental and theoretical results. The wurtzite and zinc-blende structures have a transition to rocksalt phase at the pressures of 12.7 GPa and 14 GPa, respectively. The electronic properties are calculated using both GGA and EV-GGA approximations; the obtained results by EV-GGA approximation are in much better agreement with the available experimental data. The RS phase has the largest bandgap with an amount of 4.98 eV; by increasing pressure, this amount is also increased. The optical properties like dielectric function, energy loss function, refractive index, and extinction coefficient are calculated under pressure using GGA approximation. Inter-band transitions are investigated using the peaks of imaginary part of the dielectric function and these transitions mainly occur from N-2[Formula: see text] to Al-3[Formula: see text] levels. The results show that the RS structure has more different properties than the WZ and ZB structures.

Theoretical Characterization of Thermodynamic, Magnetic and Electronic Proprieties of Full-Heusler Co2YGa (Y = V, Cr and Mn) Alloys

SPIN ◽  
2020 ◽  
Vol 10 (01) ◽  
pp. 2050005
Author(s):  
M. Mokhtari ◽  
D. Amari ◽  
F. Dahmane ◽  
G. Benabdellah ◽  
L. Zekri ◽  
...  
Keyword(s):  
Density Functional ◽  
Heusler Alloys ◽  
Debye Model ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Half Metallic ◽  
Lattice Constants ◽  
Full Heusler ◽  
Good Agreement

The electronic structure, magnetism and thermal proprieties of the full-Heusler alloys Co2YGa (Y [Formula: see text] V, Cr and Mn) have been investigated by first-principles calculations based on density functional theory with the generalized gradient approximation (GGA). Our obtained results of lattice parameters show reasonable agreement to the previously reported experimental and other theoretical studies. The calculations show that all Co2YGa (Y [Formula: see text] V, Cr and Mn) alloys belong to half-metallic compound with a magnetic moment of 2.00, 3.00 and 4.00 [Formula: see text] at their respective equilibrium lattice constants which is in good agreement with the Slater–Pauling rule and perfect 100% spin polarization at the Fermi level. The thermal effect on the macroscopic properties of these alloys is presented such as the thermal expansion coefficient, heat capacity and Debye temperature, based on the quasi-harmonic Debye model.

Computational study of the optical properties of ZnS nanoparticles

2015 ◽  
Vol 1738 ◽  
Author(s):  
M. M. Sigalas
Keyword(s):  
Density Functional Theory ◽  
Optical Properties ◽  
Density Functional ◽  
Computational Study ◽  
Time Dependent ◽  
Generalized Gradient ◽  
Zns Nanoparticles ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
The Density Functional Theory

ABSTRACTUsing the density functional theory (DFT) and time dependent DFT, within the generalized gradient approximation (GGA), the electronic and optical properties of stoichiometric (ZnS)n nanoparticles (NP) were calculated. The dependence of the gap on the size (n) of the nanoparticle will be presented. The effect of replacing S atoms with P, Se or Te atoms in the (ZnS)n nanoparticles and its influence in the gap will be also shown.

The Study on the Structural and Optical Properties of C-F Codoped Zinc Oxide from Ab Initio Calculations

2011 ◽  
Vol 311-313 ◽  
pp. 1267-1270
Author(s):  
Chun Ying Zuo ◽  
Jing Wen ◽  
Cheng Zhong ◽  
Zhong Cheng Wu ◽  
Zhong Cheng Wu
Keyword(s):  
Optical Properties ◽  
Density Functional ◽  
Lattice Mismatch ◽  
Generalized Gradient ◽  
Structural And Optical Properties ◽  
Functional Theory ◽  
Absorption Edge Shift ◽  
Pseudopotential Calculations ◽  
The Density Functional Theory ◽  
Lower Energy Region

The structural and optical properties of C-doped and C-F colonel Zoo compounds are investigated by using a first principle method with the plane wave pseudopotential calculations, based on the density functional theory(DFT), within generalized-gradient approximation (GGA). We discuss the structural properties by comparison with C-Al and C-Ga doped systems and the calculated results demonstrate that the c/a is smaller than C doped ZnO when incorporating F into the system and C-F codoping causes a smaller lattice mismatch compared with the C-Al codoped ZnO. Moreover, we focus on the complex dielectric function in order to investigate the optical properties. By analysing the results, we remark that the absorption edge shift the lower energy region(red shift) when incorporating C-F into ZnO compound.

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