scholarly journals DENSITY FUNCTIONAL THEORY STUDIES OF ELECTRONIC AND THERMAL PROPERTIES OF ZNSIP SEMICONDUCTOR

2014 ◽  
pp. 165-168
Author(s):  
S. K. TRIPATHY ◽  
V. KUMAR
Keyword(s):  
Density Functional Theory ◽  
Thermal Properties ◽  
Density Functional ◽  
Heat Of Formation ◽  
First Principles Calculation ◽  
Partial Density ◽  
Total Density ◽  
Density Of State ◽  
Functional Theory ◽  
Experimental Values

First principles calculation within density functional theory (DFT) has been used to calculate the electronic, optical and thermal properties of ZnSiP2 chalcopyrite semiconductor. The result of band structure, total density of state (DOS) and partial density of state (PDOS) have been discussed. The dielectric constant, refractive index, reflectivity, absorption coefficients, extinction coefficient and loss function have been presented in energy range of 0-25 eV. The values of melting point, Debye temperature, heat of formation and bulk modulus have been calculated. The calculated values of these parameters are in good agreement with the experimental values and the value reported by previous researchers.

scholarly journals Density functional theory study of electronic properties of Bi2Se3 and Bi2Te3

2017 ◽  
Vol 12 (3) ◽  
Author(s):  
Abdullahi Lawal ◽  
Amiruddin Shaari
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Topological Insulators ◽  
Van Der Waals Interactions ◽  
Partial Density ◽  
Total Density ◽  
Density Of State ◽  
Generalized Gradient ◽  
Linear Dispersion ◽  
Functional Theory

Topological insulators are layered materials via van der Waals interactions with hexagonal unit cell similar to that of graphene. The exciting features of Bi2Se3 and Bi2Te3 topological insulators their zero band gap surface states exhibiting linear dispersion at the Fermi energy. We present here first principles study pertaining to electronics properties of Bi2Se3 and Bi2Te3 compound with and without spin-orbit interaction using density functional theory (DFT). Total density of state (DOS), partial density of state (PDOS) and band structure where determined by Quantum-Espresso simulation package which uses plane wave basis and pseudopotential for the core electrons, while treating exchange-correlation potential with generalized gradient approximation (GGA). From our computations, the obtained results were found to be consistent with the available experimental results. 

Research for Photoelectric Property of SnO2 Vacancy Doped Cu

2014 ◽  
Vol 1070-1072 ◽  
pp. 612-615
Author(s):  
Bang Jian Zhang ◽  
Feng Miao
Keyword(s):  
Density Functional Theory ◽  
Optical Properties ◽  
Electronic Structure ◽  
Fermi Level ◽  
Density Functional ◽  
Photoelectric Property ◽  
Partial Density ◽  
Complex Dielectric Function ◽  
Density Of State ◽  
Functional Theory

Based on Density Functional Theory, we investigated electronic structure and optical properties of Cu vacancy doped SnO2 with density of 4.35%, including the density of state(dos), the partial density of state(PDOS) and complex dielectric function. The results show that Fermi level access valence band with the increase of doped density. And this can attributed to the increased folded state. It has enhanced the electrical and metal property of material.

scholarly journals Electronic Structure of the CuCl2(100) Surface: A DFT First-Principle Study

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Sherin A. Saraireh ◽  
Mohammednoor Altarawneh
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Bond Angle ◽  
Structural Parameters ◽  
First Principle ◽  
Slab Model ◽  
Density Of State ◽  
Functional Theory ◽  
Principle Density Functional Theory ◽  
Experimental Values

First-principle density functional theory (DFT) and a periodic-slab model have been utilized to investigate the structure of the CuCl2(100) surface. Structural parameters of the bulk CuCl2are reported and compared with the experimental values. The structure of the CuCl2(100) is calculated using a () supercell. Structural parameters in terms of bond lengths and bond angle are calculated. Electronic properties of the CuCl2(100) surface are investigated by calculating the density of state (DOS) and the projected density of state for a slab containing five layers.

First-principle investigations on structural, elastic, electronic and thermodynamic properties of ScX3(X = Ir,Pd,Pt and Rh) under high pressure

2015 ◽  
Vol 29 (32) ◽  
pp. 1550201 ◽  
Author(s):  
Bao Chen ◽  
Santao Qi ◽  
Hongquan Song ◽  
Chuanhui Zhang ◽  
Jiang Shen
Keyword(s):  
Density Functional Theory ◽  
Thermodynamic Properties ◽  
Bulk Modulus ◽  
Density Functional ◽  
External Pressure ◽  
First Principle ◽  
Zero Temperature ◽  
Functional Theory ◽  
Change Trend ◽  
Experimental Values

In this paper, the structural, elastic, electronic and thermodynamic properties of [Formula: see text] and [Formula: see text] intermetallic compound are investigated using pseudopotential method based on density functional theory (DFT) under pressure. In this work, the calculated lattice constant and bulk modulus are in accordance with experimental values at zero temperature and zero pressure. The bulk modulus [Formula: see text], shear modulus [Formula: see text] and Young’s modulus [Formula: see text] for [Formula: see text] and [Formula: see text] increase with the increasing external pressure. It is noted that [Formula: see text] of investigated compound has the largest [Formula: see text], [Formula: see text] and [Formula: see text]. The results of [Formula: see text] and [Formula: see text] have the same change trend, but [Formula: see text] presents an irregular change for [Formula: see text] and [Formula: see text]. The density of states for [Formula: see text] and [Formula: see text] are investigated at 0, 30 and 50 GPa. In addition, the thermodynamic properties as a function of temperature at different pressure are also studied.

scholarly journals Structural, elastic, electronic and thermal properties of InAs: A study of functional density

2017 ◽  
Vol 26 (46) ◽  
Author(s):  
Víctor Mendoza-Estrada ◽  
Melissa Romero-Baños ◽  
Viviana Dovale-Farelo ◽  
William López-Pérez ◽  
Álvaro González-García ◽  
...  
Keyword(s):  
Thermal Properties ◽  
Density Functional ◽  
Experimental Studies ◽  
Debye Model ◽  
Band Gap Energy ◽  
Functional Theory ◽  
Zinc Blende ◽  
The Density Functional Theory ◽  
The Stability ◽  
Experimental Values

In this research, first-principles calculations were carried out within the density functional theory (DFT) framework, using LDA and GGA, in order to study the structural, elastic, electronic and thermal properties of InAs in the zinc-blende structure. The results of the structural properties (a, B0, ) agree with the theoretical and experimental results reported by other authors. Additionally, the elastic properties, the elastic constants (C11, C12 and C44), the anisotropy coefficient (A) and the predicted speeds of the sound ( , , and ) are in agreement with the results reported by other authors. In contrast, the shear modulus (G), the Young's modulus (Y) and the Poisson's ratio (v) show some discrepancy with respect to the experimental values, although, the values obtained are reasonable. On the other hand, it is evident the tendency of the LDA and GGA approaches to underestimate the value of the band-gap energy in semiconductors. The thermal properties (V, , θD yCV) of InAs, calculated using the quasi-harmonic Debye model, are slightly sensitive as the temperature increases. According to the stability criteria and the negative value of the enthalpy of formation, InAs is mechanically and thermodynamically stable. Therefore, this work can be used as a future reference for theoretical and experimental studies based on InAs.

scholarly journals Pt Cluster Modified h-BN for Gas Sensing and Adsorption of Dissolved Gases in Transformer Oil: A Density Functional Theory Study

Nanomaterials ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1746 ◽  
Author(s):  
Yingang Gui ◽  
Tao Li ◽  
Xin He ◽  
Zhuyu Ding ◽  
Pingan Yang
Keyword(s):  
Density Functional Theory ◽  
Density Of States ◽  
Density Functional ◽  
Hexagonal Boron Nitride ◽  
Energy Charge ◽  
Boron Nitride Nanotubes ◽  
Transformer Oil ◽  
Total Density ◽  
Functional Theory ◽  
Pt Cluster

Hexagonal-Boron nitride nanotubes (h-BN) decorated with transition metals have been widely studied due to their enhanced physicochemical properties. In this paper, Pt cluster-modified h-BN is proposed as a sensitive material for a novel gas sensor for the online malfunction monitoring of oil-immersed transformers. The inner oil is ultimately decomposed to various gases during the long-term use of oil-immersed transformers. Exposure to excessively high temperatures produces the alkanes CH4 and C2H6, whereas different degrees of discharge generate H2 and C2H2. Therefore, the identification of H2, CH4, and C2H2 gas efficiently measures the quality of transformers. Based on the density functional theory, the most stable h-BN doped with 1–4 Pt atoms is employed to simulate its adsorption performance and response behavior to these typical gases. The adsorption energy, charge transfer, total density of states, projected density of states, and orbital theory of these adsorption systems are analyzed and the results show high consistency. The adsorption ability for these decomposition components are ordered as follows: C2H2 > H2 > CH4. Pt cluster-modified h-BN shows good sensitivity to C2H2, H2, with decreasing conductivity in each system, but is insensitive to CH4 due to its weak physical sorption. The conductivity change of Ptn-h-BN is considerably larger upon H2 than that upon C2H2, but is negligible upon CH4. Our calculations suggest that Pt cluster modified h-BN can be employed in transformers to estimate their operation status.

Oxides, Silicides, and Silicates of Zirconium and Hafnium; Density Functional Theory Study

2002 ◽  
Vol 716 ◽  
Author(s):  
Maciej Gutowski ◽  
John E. Jaffe ◽  
Chun-Li Liu ◽  
Matt Stoker ◽  
Anatoli Korkin
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Gate Dielectric ◽  
Density Functional Theory Calculations ◽  
Heat Of Formation ◽  
Density Functional Theory Study ◽  
Functional Theory ◽  
Exchange Correlation ◽  
The Difference ◽  
Constituent Elements

AbstractIt is known that the chemistries of hafnium and zirconium are more nearly identical than for any other two congeneric elements. Thus, both zirconia and hafnia, with the dielectric constant K > 20, have emerged as potential replacements for silica (K = 3.9) as a gate dielectric. We report an important difference between the zirconia/Si and hafnia/Si interfaces based on density functional theory calculations with the Perdew-Wang 91 exchange-correlation functional on the oxides, silicides, and silicates of Zr and Hf. The zirconia/Si interface has been found to be unstable with respect to formation of silicides whereas the hafnia/Si interface is stable. The difference between the two interfaces results from the fact that HfO2 is more stable than ZrO2 (i.e. has a larger heat of formation from its constituent elements) by more than 53 kJ/mol. The hafnium silicides, on the other hand, are less stable than zirconium silicides by ca. 20 kJ/mol.

Sign in / Sign up

Export Citation Format

Share Document