Polyimide Electronic Structural and Optical Properties from First Principles Calculations

The electronic structural and optical properties of Polyimide (PI) are studied by first principle method of density theory. It is shown that molecules orbit contribution of PI is derived from carbon 2p orbital and oxygen 2p orbital, respectively,and the band gap from the energy band structure is much smaller than that of the experimental value. It is also found that the band gap calculated from the absorption edge of absorption spectra is in agreement with the result of the energy band structure. Furthermore, the relationship between the formation of dielectric function peaks and other spectral characteristics is interpreted.

Download Full-text

The Optical Properties, Energy Band Structure, and Interfacial Conductance of a 3C-SiC(111)/Si(111) Heterostructure Grown by the Method of Atomic Substitution

Technical Physics Letters ◽

10.1134/s1063785020110243 ◽

2020 ◽

Vol 46 (11) ◽

pp. 1103-1106 ◽

Cited By ~ 1

Author(s):

S. A. Kukushkin ◽

A. V. Osipov

Keyword(s):

Optical Properties ◽

Band Structure ◽

Energy Band ◽

Energy Band Structure ◽

Atomic Substitution

Download Full-text

First-Principles Study on the Stabilities, Electronic and Optical Properties of GexSn1-xSe Alloys

Nanomaterials ◽

10.3390/nano8110876 ◽

2018 ◽

Vol 8 (11) ◽

pp. 876 ◽

Cited By ~ 1

Author(s):

Qi Qian ◽

Lei Peng ◽

Yu Cui ◽

Liping Sun ◽

Jinyan Du ◽

...

Keyword(s):

Optical Properties ◽

Solar Cells ◽

Band Gap ◽

Electronic Properties ◽

First Principles ◽

Future Application ◽

First Principles Calculations ◽

Electronic And Optical Properties ◽

Direct Bandgap ◽

The Future

We systematically study, by using first-principles calculations, stabilities, electronic properties, and optical properties of GexSn1-xSe alloy made of SnSe and GeSe monolayers with different Ge concentrations x = 0.0, 0.25, 0.5, 0.75, and 1.0. Our results show that the critical solubility temperature of the alloy is around 580 K. With the increase of Ge concentration, band gap of the alloy increases nonlinearly and ranges from 0.92 to 1.13 eV at the PBE level and 1.39 to 1.59 eV at the HSE06 level. When the Ge concentration x is more than 0.5, the alloy changes into a direct bandgap semiconductor; the band gap ranges from 1.06 to 1.13 eV at the PBE level and 1.50 to 1.59 eV at the HSE06 level, which falls within the range of the optimum band gap for solar cells. Further optical calculations verify that, through alloying, the optical properties can be improved by subtle controlling the compositions. Since GexSn1-xSe alloys with different compositions have been successfully fabricated in experiments, we hope these insights will contribute to the future application in optoelectronics.

Download Full-text

Identifying and rationalizing the morphological, structural, and optical properties of β-Ag2MoO4 microcrystals, and the formation process of Ag nanoparticles on their surfaces: combining experimental data and first-principles calculations

Science and Technology of Advanced Materials ◽

10.1088/1468-6996/16/6/065002 ◽

2015 ◽

Vol 16 (6) ◽

pp. 065002 ◽

Cited By ~ 47

Author(s):

Maria T Fabbro ◽

Carla Saliby ◽

Larissa R Rios ◽

Felipe A La Porta ◽

Lourdes Gracia ◽

...

Keyword(s):

Experimental Data ◽

Optical Properties ◽

First Principles ◽

Formation Process ◽

Ag Nanoparticles ◽

First Principles Calculations ◽

Structural And Optical Properties

Download Full-text

Electronic Structure and Optical Properties of SrTi0.5Zr0.5O3

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.846-847.1919 ◽

2013 ◽

Vol 846-847 ◽

pp. 1919-1922

Author(s):

Hong Liang Pan ◽

Teng Li ◽

Shi Liang Yang ◽

Yi Ming Liu

Keyword(s):

Optical Properties ◽

Band Structure ◽

Energy Band ◽

Electronic Energy ◽

Energy Band Structure ◽

Generalized Gradient ◽

Generalized Gradient Approximation ◽

Structure Density ◽

Pseudo Potential ◽

Electronic Energy Band

The electronic-energy band structure and optical properties of SrTi0.5Zr0.5O3are calculated by the pseudo-potential plane wave (PP-PW) mehod with the generalized gradient approximation (GGA). The energy band structure, density of states (DOS) are obtained. The optical properties including the dielectric function, reflectivity, absorption spectrum, extinction coefficient, energy-loss spectrum and refractive index are also discussed.

Download Full-text

Energy-Band Structure and Optical Properties of GaSb,

Physical Review B ◽

10.1103/physrevb.1.2827.2 ◽

1970 ◽

Vol 1 (6) ◽

pp. 2827-2827

Author(s):

H. I. Zhang ◽

J. Callaway

Keyword(s):

Optical Properties ◽

Band Structure ◽

Energy Band ◽

Energy Band Structure

Download Full-text

First-principles studies on electronic structures and optical properties of two-dimensional Sn1−xTi(Zr)xS2 alloys

Modern Physics Letters B ◽

10.1142/s0217984918500926 ◽

2018 ◽

Vol 32 (07) ◽

pp. 1850092 ◽

Cited By ~ 1

Author(s):

Dandan Li ◽

Juan Du ◽

Qian Zhang ◽

Congxin Xia ◽

Shuyi Wei

Keyword(s):

Optical Properties ◽

Band Gap ◽

First Principles ◽

Electronic Structures ◽

Threshold Energy ◽

Ternary Alloys ◽

Two Dimensional ◽

First Principles Calculations ◽

Experimental Conditions ◽

Part Formula

Through first-principles calculations we study the electronic structures and optical properties of two-dimensional (2D) Sn[Formula: see text]Ti(Zr)[Formula: see text]S2 alloys. The results indicate that the band gap value of Sn[Formula: see text]Ti(Zr)[Formula: see text]S2 alloys is decreased continuously when Ti(Zr) concentration is increased, which is very beneficial to optoelectronic devices applications. Moreover, the static dielectric constant is increased when the Ti(Zr) concentration is increased in the 2D Sn[Formula: see text]Ti(Zr)[Formula: see text]S2 alloys. In addition, we also calculate the imaginary part [Formula: see text] dispersion of Sn[Formula: see text]Ti(Zr)[Formula: see text]S2 alloys along the plane with different Ti(Zr) concentrations. The threshold energy values decrease with increasing Ti(Zr) concentrations in the Sn[Formula: see text]Ti(Zr)[Formula: see text]S2 ternary alloys. Moreover, the calculations of formation energy also indicate that these 2D alloys can be fabricated under some experimental conditions. These results suggest that Ti(Zr) substituting Sn atom is an efficient way to tune the band gap and optical properties of 2D SnS2 nanosheets.

Download Full-text

Electronic Structure, Effective Masses and Optical Properties of Monoclinic HfO2 from First-Principles Calculations

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.216.341 ◽

2011 ◽

Vol 216 ◽

pp. 341-344 ◽

Cited By ~ 2

Author(s):

Qi Jun Liu ◽

Zheng Tang Liu ◽

Li Ping Feng

Keyword(s):

Optical Properties ◽

Electronic Structure ◽

Band Structure ◽

First Principles ◽

Density Functional ◽

First Principles Calculations ◽

Functional Theory ◽

Effective Masses ◽

Indirect Band Gap ◽

Calculated Equilibrium

Electronic structure, effective masses and optical properties of monoclinic HfO2were studied using the plane-wave ultrasoft pseudopotential technique based on the first-principles density-functional theory (DFT). The calculated equilibrium lattice parameters are in agreement with the previous works. From the band structure, the effective masses and optical properties are obtained. The calculated band structure shows that monoclinic HfO2has indirect band gap and all of the effective masses of electrons and holes are less than that of a free electron. The peaks position distributions of imaginary parts of the complex dielectric function have been explained according to the theory of crystal-field and molecular-orbital bonding.

Download Full-text