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

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.

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First-principles study on structural, elastic and thermal properties of γ-TiAl and α2-Ti3Al phases in TiAl-based alloy under high pressure

International Journal of Modern Physics B ◽

10.1142/s0217979217500795 ◽

2017 ◽

Vol 31 (11) ◽

pp. 1750079 ◽

Cited By ~ 7

Author(s):

Chaoyan Zhang ◽

Hua Hou ◽

Yuhong Zhao ◽

Xiaomin Yang ◽

Yaqiong Guo

Keyword(s):

High Pressure ◽

Thermal Properties ◽

Density Functional ◽

Theoretical Data ◽

Debye Model ◽

Functional Theory ◽

The Density Functional Theory ◽

Two Phases ◽

Calculated Equilibrium ◽

Good Agreement

The structural, elastic and thermal properties of [Formula: see text]-TiAl and [Formula: see text]-Ti3Al phases in the TiAl-based alloy under pressure were reported using CASTEP program based on the density functional theory. The calculated equilibrium parameters and elastic constants are in good agreement with experimental and the available theoretical data. The results indicate that under the same pressure, the [Formula: see text] phase in the direction along [Formula: see text]-axis is easier to be compressed than the [Formula: see text] phase, while the compression along [Formula: see text]-axis of [Formula: see text] phase is larger than that of [Formula: see text] phase; when the pressure is below 20 GPa, both the two phases are elastically stable, but the [Formula: see text] phase have higher shear modulus and Young’s modulus, and the [Formula: see text] phase has better ductility and plasticity. Debye temperature, bulk modulus, thermal expansion coefficient and heat capacity of the [Formula: see text] phase and [Formula: see text] phase under high pressure and high temperature were also successfully calculated and compared using the quasi-harmonic Debye model in the present work.

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Structural and elastic properties of ZrN and HfN: ab initio study

Canadian Journal of Physics ◽

10.1139/cjp-2013-0377 ◽

2014 ◽

Vol 92 (9) ◽

pp. 1058-1061 ◽

Cited By ~ 4

Author(s):

Anurag Srivastava ◽

Bhoopendra Dhar Diwan

Keyword(s):

Elastic Properties ◽

Density Functional ◽

Zirconium Nitride ◽

Energy Calculation ◽

Generalized Gradient ◽

Functional Theory ◽

Hafnium Nitride ◽

Zinc Blende ◽

The Density Functional Theory ◽

The Stability

The present paper discusses the density functional theory based stability analysis of zirconium nitride and hafnium nitride in its rocksalt (B1), CsCl (B2), and zinc blende (B3) type phases. The ground state total energy calculation approach of the system has been used through the generalized gradient approximation parameterized with revised Perdew–Burke–Ernzerhof as exchange correlation functional. The present theoretical analysis confirms the stability trend of phases from most stable to less stable as B1 → B2 → B3. The study also reports the analysis of elastic properties of these nitrides in its most stable B1-type phase.

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CHARGE STABILITY AND CONDUCTANCE ANALYSIS OF ANTHRACENE-BASED SINGLE ELECTRON TRANSISTOR

International Journal of Nanoscience ◽

10.1142/s0219581x13500452 ◽

2013 ◽

Vol 12 (06) ◽

pp. 1350045 ◽

Cited By ~ 14

Author(s):

ANURAG SRIVASTAVA ◽

BODDEPALLI SANTHIBHUSHAN ◽

PANKAJ DOBWAL

Keyword(s):

Coulomb Blockade ◽

Density Functional ◽

Stability Diagram ◽

Single Electron ◽

Single Electron Transistor ◽

Functional Theory ◽

Charge Stability ◽

Anthracene Molecule ◽

The Stability ◽

Experimental Values

The present paper discusses the investigation of electronic properties of anthracene-based single electron transistor (SET) operating in coulomb blockade region using Density Functional Theory (DFT) based Atomistix toolkit-Virtual nanolab. The charging energies of anthracene molecule in isolated as well as electrostatic SET environments have been calculated for analyzing the stability of the molecule for different charge states. Study also includes the analysis of SET conductance dependence on source/drain and gate potentials in reference to the charge stability diagram. Our computed charging energies for anthracene in isolated environment are in good agreement with the experimental values and the proposed anthracene SET shows good switching properties in comparison to other acene series SETs.

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Study of the Stability and Chemical Reactivity of a Series of Tetrazole Pyrimidine Hybrids by the Density Functional Theory Method (DFT)

Oriental Journal Of Chemistry ◽

10.13005/ojc/370406 ◽

2021 ◽

Vol 37 (4) ◽

pp. 805-812

Author(s):

Ahissandonatien Ehouman ◽

Adjoumanirodrigue Kouakou ◽

Fatogoma Diarrassouba ◽

Hakim Abdel Aziz Ouattara ◽

Paulin Marius Niamien

Keyword(s):

Density Functional ◽

Theoretical Study ◽

Molecular Descriptors ◽

Chemical Reactivity ◽

Density Functional Theory Method ◽

Functional Theory ◽

Reactivity Descriptors ◽

The Density Functional Theory ◽

The Stability ◽

Global Reactivity Descriptors

Our theoretical study of stability and reactivity was carried out on six (06) molecules of a series of pyrimidine tetrazole hybrids (PTH) substituted with H, F, Cl, Br, OCH3 and CH3 atoms and groups of atoms using the density function theory (DFT). Analysis of the thermodynamic formation quantities confirmed the formation and existence of the series of molecules studied. Quantum chemical calculations at the B3LYP / 6-311G (d, p) level of theory determined molecular descriptors. Global reactivity descriptors were also determined and analyzed. Thus, the results showed that the compound PTH_1 is the most stable, and PTH_5 is the most reactive and nucleophilic. Similarly, the compound PTH_4 is the most electrophilic. The analysis of the local descriptors and the boundary molecular orbitals allowed us to identify the preferred atoms for electrophilic and nucleophilic attacks.

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Pressure effect on the structural, phonon, elastic and thermodynamic properties of L12phase RH3TA: First-principles calculations

International Journal of Modern Physics B ◽

10.1142/s0217979218501692 ◽

2018 ◽

Vol 32 (14) ◽

pp. 1850169

Author(s):

Leini Wang ◽

Zhang Jian ◽

Wei Ning

Keyword(s):

Thermodynamic Properties ◽

Density Functional ◽

Harmonic Approximation ◽

Debye Model ◽

Approximation Model ◽

Functional Theory ◽

The Density Functional Theory ◽

Relationship Of ◽

G Ratio ◽

Wide Pressure

The phonon, elastic and thermodynamic properties of L12phase Rh3Ta have been investigated by the density functional theory (DFT) approach combined with the quasi-harmonic approximation model. The results of the phonon band structure show that L12phase Rh3Ta possesses dynamical stability in the pressure range from 0–80 GPa due to the absence of imaginary frequencies. The pressure dependences with the elastic constants C[Formula: see text], shear modulus G, bulk modulus B, Young’s modulus Y, Poisson’s ratio and B/G ratio have been analyzed. The results of the elastic properties studies show that L12phase Rh3Ta compound is mechanically stable and possesses a higher hardness, improved ductility and plasticity under higher pressures. The pressure and temperature relationship of the thermodynamic properties, such as the Debye temperature [Formula: see text], heat capacity C[Formula: see text], thermal expansion coefficient [Formula: see text] and the Grüneisen parameter [Formula: see text] are predicted by the quasi-harmonic Debye model in a wide pressure (0–80 GPa) and temperature (0–750 K) ranges.

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Density Functional Theory Calculations of Properties of the Grain Boundaries in Aluminum

MRS Proceedings ◽

10.1557/opl.2011.531 ◽

2011 ◽

Vol 1297 ◽

Cited By ~ 2

Author(s):

Marek Muzyk ◽

Krzysztof J. Kurzydlowski

Keyword(s):

Density Functional Theory ◽

Grain Boundaries ◽

Density Functional ◽

Quantitative Description ◽

Aluminum Matrix ◽

Density Functional Theory Calculations ◽

Functional Theory ◽

Nano Crystalline ◽

The Density Functional Theory ◽

The Stability

ABSTRACTThe Density Functional Theory has been used to analyze an inter-granular segregation of Cu and Mg. The stability of Cu and Mg atoms in the aluminum matrix, intermetallic phases and symmetric twist grain boundaries has been compared. The quantitative description of solubility of Cu and Mg atoms in the nano-crystalline aluminum has been proposed. The calculations have been carried out to investigate the properties of symmetric twist boundaries in aluminum with and without Cu/Mg atoms. The phenomena of are discussed and its effect on the stability of precipitates containing these elements.

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Influences of Fe Doping on the Electronic Structure of Mg(0001) Surface and Hydrogenation Mechanism in Fe-Doped Mg(0001) Surface

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.873.114 ◽

2013 ◽

Vol 873 ◽

pp. 114-120 ◽

Cited By ~ 3

Author(s):

Zhi Wen Wang ◽

Xin Jun Guo ◽

Hong Xia Zhang ◽

Li Li

Keyword(s):

Density Functional ◽

Hydrogen Molecule ◽

Functional Theory ◽

Practical Applications ◽

Atom Diffusion ◽

Charge Density Difference ◽

The Density Functional Theory ◽

Diffusion Paths ◽

The Stability ◽

Dissociation Path

First-principles calculations within the density functional theory (DFT) have been carried out to study the interaction of hydrogen molecule with Fe-doped Mg (0001) surfaces. First we have calculated the stability of the Fe atom on the Mg surface, On the basis of the energetic criteria, Fe atom prefer to substitute one of the Mg atoms from the second layer. In the second step, we have studied the interaction between hydrogen molecule and the Fe-doped Mg (0001) surface. The results show that for Fe atoms doped Mg (0001) surface in the second layer, enhances the chemisorption interaction between H2molecule and Fe atom, but also benefits H atom diffusion into Mg bulk with relatively more diffusion paths compared with that of clean Mg surface. Charge density difference plots provided some ideas about why certain alloying elements on the surface reduce the energy barrier of H2molecule dissociation on Fe-doped Mg (0001) surface. We can see that Fe as catalyst for the hydrogenation/dehydrogenation of Mg alloy samples and provide more dissociation path for H2molecule and diffusion paths for H atom, The present results not only beneficial for clarify the experimentally observed fast hydrogenation kinetics for Fe-capped Mg materials but also help to design new types of hydrogen storage materials for practical applications in the auto industry.

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THEORETICAL STUDY OF THE BAND GAP OF SrSe AND SrTe IN GW APPROXIMATION

Modern Physics Letters B ◽

10.1142/s0217984911027121 ◽

2011 ◽

Vol 25 (23) ◽

pp. 1905-1914

Author(s):

XIAO LING ZHU ◽

HONG ZHANG ◽

XIN LU CHENG

Keyword(s):

Band Gap ◽

Density Functional ◽

Theoretical Study ◽

Generalized Gradient ◽

Gw Approximation ◽

Functional Theory ◽

The Density Functional Theory ◽

Structural And Electronic Properties ◽

Experimental Values ◽

Interaction Approximation

Using the first-principles pseudopotential method within a generalized gradient approximation of the density functional theory, the structural and electronic properties of SrSe and SrTe have been studied. The calculated lattice parameters are in excellent agreement with experimental values, whereas the error in the minimum gap value is as high as 43.25% in SrSe . To get reliable band gap values of SrSe and SrTe , we employ the GW (G is the Green's function and W is the screened Coulomb interaction) approximation method. The result in GW approximation improves the band gap value of the SrSe greatly and agrees with the value of experimental measurement.

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The difference in stability between 5′R and 5′S diastereomers of 5′,8-cyclopurine-2′-deoxynucleosides. DFT study in gaseous and aqueous phase

Open Chemistry ◽

10.2478/s11532-009-0104-1 ◽

2010 ◽

Vol 8 (1) ◽

pp. 134-141 ◽

Cited By ~ 1

Author(s):

Boleslaw Karwowski

Keyword(s):

Density Functional ◽

Bond Cleavage ◽

Basis Set ◽

Small Range ◽

Functional Theory ◽

The Density Functional Theory ◽

Formic Acid Hydrolysis ◽

The Difference ◽

The Stability ◽

First Time

AbstractOxidatively generated damage to DNA frequently appears in the human genome as an effect of aerobic metabolism or as the result of exposure to exogenous oxidizing agents. Due to these facts it has been decided to calculate the stability of 5′,8-cyclo-2′-deoxyadenosine/guanosine (cdA, cdG) in their 5′R and 5′S diastereomeric forms. For all points of quantum mechanics studies presented, the density functional theory (DFT) with B3LYP parameters on 6-311++G** basis set level was used. The calculations showed a significant negative enthalpy for glycosidic bond cleavage reaction for cationic forms and slightly negative for neutral ones. The preliminary study of the discussed process has shown the nature of stepwise nucleophilic substitution DN*AD type mechanism. Surprisingly, the different values in free energy, between short-lived oxacarbenium ion intermediates, have been found to lie over a relatively small range, around 1 and 2.8 kcal mol−1. For anions, the decomposition enthalpies were found as positive in aqueous phases. These theoretical results are supported by the formic acid hydrolysis experiments of both diastereomers of cdA, for the first time. (5′S)cdA exhibited higher stability than (5′R)cdA.

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First-principle study of the electronic structure and optical property of Nb-doped anatase TiO2

International Journal of Modern Physics B ◽

10.1142/s021797921450091x ◽

2014 ◽

Vol 28 (17) ◽

pp. 1450091

Author(s):

Q. Y. Hou ◽

Q. L. Liu ◽

C. W. Zhao ◽

Y. Zhang

Keyword(s):

Electronic Structure ◽

Optical Property ◽

Band Gap ◽

Absorption Edge ◽

Short Wavelength ◽

Density Functional ◽

Functional Theory ◽

Long Wavelength ◽

The Density Functional Theory ◽

The Stability

The absorption edge shifted to long wavelength direction and short wavelength direction of two opposite experimental conclusions have been reported, when the band-gap and absorption spectra of Nb -doped anatase TiO 2 were studied. In order to solve this contradiction, the electronic structure and the optical property of Nb heavy doped anatase TiO 2 have been studied by the first-principles plane-wave ultrasoft pseudopotential method based on the density functional theory with +U method modification. The calculated results indicate that the higher the Nb -doping is, the higher the total energy is, the worse the stability is, the higher the formation energy is, the more difficult the doping is, the wider the optical band-gap is, the more obvious the absorption edge shifting to short wavelength direction is, the lower the absorptivity and the reflectivity is, which is in agreement with the experimental results. The reasonable interpretation of the contradiction has been reported in this paper, too.

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