First Principles Study of Cerium Monochalcogenides

A theoretical investigation of structural, magnetic, electronic, and lattice dynamical properties of cerium monochalcogenides using the generalized gradient approximation (GGA) +Uwithin ultrasoft pseudopotentials and a plane-wave basis is presented. All the calculated quantities, except the local magnetic moments, are found to be in good agreement with the experimental data. The lattice dynamical results indicate a strong chalcogenide dependence for the anomalous features of the phonon dispersions.

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Study of the enhanced electronic and thermoelectric (TE) properties of ZrxHf1−x−yTayNiSn: a first principles study

RSC Advances ◽

10.1039/c5ra12897h ◽

2015 ◽

Vol 5 (115) ◽

pp. 95353-95359 ◽

Cited By ~ 23

Author(s):

D. P. Rai ◽

A. Shankar ◽

Sandeep Sandeep ◽

M. P. Ghimire ◽

R. Khenata ◽

...

Keyword(s):

Density Functional Theory ◽

First Principles ◽

Density Functional ◽

Generalized Gradient ◽

Functional Theory ◽

Generalized Gradient Approximation ◽

First Principles Study

A density functional theory (DFT) approach employing generalized gradient approximation (GGA) and the modified Becke Johnson (TB-mBJ) potential has been used to study the electronic and thermoelectric (TE) properties of ZrxHf1−x−yTayNiSn.

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First Principles Calculations on Cu-Doped TiO2

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1101.70 ◽

2015 ◽

Vol 1101 ◽

pp. 70-74 ◽

Cited By ~ 1

Author(s):

Waqas Mahmood

Keyword(s):

Optical Properties ◽

Plane Wave ◽

First Principles ◽

Geometry Optimization ◽

Titanium Atom ◽

Mesh Size ◽

First Principles Calculations ◽

Generalized Gradient ◽

Generalized Gradient Approximation ◽

Cutoff Energy

The electronic and optical properties of tetragonal rutile TiO2 are investigated by first principles calculations using plane-wave pseudopotentials. Generalized gradient approximation proposed by Perdew-Burke-Ernzerhof (GGA-PBE) is employed with Vanderbilt’s ultrasoft pseudopotentials (USPs) for the geometry optimization. The cutoff energy 380 eV and Monkhorst-Pack (MP) grid of size 5 x 5 x 8 is used to study the electronic properties of TiO2. Besides, the optical properties of TiO2 are studied using a mesh size of 9 x 9 x 9. A periodic supercell of size 2a x 2b x 2c is created and a single Copper (Cu) atom directly substitutes the titanium atom. The geometry is optimized at cutoff energy 440 eV with MP grid of size 3 x 3 x 8 and a denser k-points mesh of size 6 x 6 x 6 is used for the investigation of optical properties.

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First-principles investigation of the elastic and thermodynamic properties of ReC2 (Re = Ho, Nd, Pr)

Modern Physics Letters B ◽

10.1142/s021798491450256x ◽

2015 ◽

Vol 29 (01) ◽

pp. 1450256 ◽

Cited By ~ 1

Author(s):

Wen Huang ◽

Haichuan Chen

Keyword(s):

Experimental Data ◽

Thermodynamic Properties ◽

First Principles ◽

Density Functional ◽

Elastic Anisotropy ◽

Generalized Gradient ◽

Functional Theory ◽

Lattice Constants ◽

Generalized Gradient Approximation ◽

Temperature Melting

The elastic and thermodynamic properties of Re C 2 (Re = Ho , Nd , Pr ) have been investigated by using the first-principles density functional theory within the generalized gradient approximation. The computed lattice constants of Re C 2 are in agreement with the experimental data. The calculated elastic constants reveal that all compounds are mechanically stable. The shear modulus, Young's modulus, Poisson's ratio σ, the ratio B/G, shear anisotropy and elastic anisotropy are also calculated. Finally, the Vicker hardness, Debye temperature, melting point and thermal conductivity have been predicted.

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Optical Properties of β-Si3N4 Studied from First-Principles Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.490-495.3253 ◽

2012 ◽

Vol 490-495 ◽

pp. 3253-3256 ◽

Cited By ~ 1

Author(s):

Dong Chen ◽

Kui Yang

Keyword(s):

Optical Properties ◽

First Principles ◽

Theoretical Study ◽

Potential Method ◽

First Principles Calculations ◽

Generalized Gradient ◽

Generalized Gradient Approximation ◽

Near Future ◽

Pseudo Potential ◽

Good Agreement

A detailed theoretical study of the optical properties of β-Si3N4 has been carried out by means of first-principles calculations using the plane-wave pseudo-potential method with generalized gradient approximation for the exchange and correlation functional. The calculated maximum absorption coefficient is 312000, which is in good agreement with the other calculated result. β-Si3N4 can be used as a photo-electronic material because its absorption curve has an abrupt limit at low energy region. The light beam with the frequency of 7eV～15eV can easily traverse the β-Si3N4 crystal. For the dielectric function, the strongest peaks are located at 6.5 and 9.0eV for the real and imaginary parts, respectively. Moreover, the calculated static dielectric constant is 3.21. Actually speaking, our calculated results should be testified by experiments in the near future.

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First Principles Study on Structural, Electronic, Elastic and Thermal Properties of OsAl and OsSi

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1047.71 ◽

2014 ◽

Vol 1047 ◽

pp. 71-77 ◽

Cited By ~ 1

Author(s):

Nikita Acharya ◽

Bushra Fatima ◽

Sunil Singh Chouhan ◽

Sankar P. Sanyal

Keyword(s):

Thermal Properties ◽

First Principles ◽

Full Potential ◽

Generalized Gradient ◽

Pressure Derivative ◽

Plane Wave Method ◽

Lattice Constants ◽

First Principles Study ◽

First Time ◽

Good Agreement

First - principles study on structural, electronic, elastic and thermal properties of B2phase OsAl and OsSi have been reported usingab-initio full potential linearized plane wave method (FP-LAPW) method within generalized gradient approximation (GGA). We have calculated ground state and electronic properties such as lattice constant (a0), bulk modulus (B0), its pressure derivative (B0') and density of states at Fermi level N(EF). Lattice constants are in good agreement with other results. The elastic constants (C11, C12and C44) are also calculated for these compounds. Ductility has been analyzed by Pugh’s rule (B/GH) ratio and Cauchy’s pressure (C12-C44). To the best of our knowledge, these properties are calculated first time.

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First-Principles Investigation of ThO2

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.535-537.2531 ◽

2012 ◽

Vol 535-537 ◽

pp. 2531-2534 ◽

Cited By ~ 1

Author(s):

Ya Ping Li ◽

Ping Qian ◽

Li Jun Bai ◽

Jin Chun Li ◽

Jiang Shen

Keyword(s):

Experimental Data ◽

First Principles ◽

Energy Band ◽

Local Density Approximation ◽

Local Density ◽

Lattice Parameter ◽

Density Approximation ◽

Generalized Gradient ◽

Generalized Gradient Approximation ◽

Densities Of States

We systematically performed first-principles investigations of the structural properties, electron energy band, and densities of states (DOS) for ThO2. All calculations were carried out using the local density approximation (LDA), generalized gradient approximation (GGA), LDA+U, and GGA+U approaches. We also compared our findings with experimental data and other calculations. The lattice parameter obtained using the GGA+U agrees well with the experimental value.

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First-Principles Study of Structural and Thermal of α-Ni4N

Materials Science Forum ◽

10.4028/www.scientific.net/msf.817.719 ◽

2015 ◽

Vol 817 ◽

pp. 719-724 ◽

Cited By ~ 1

Author(s):

Hai Jun Hou ◽

Hua Jun Zhu ◽

Xiao Liang ◽

Lin Hua Xie

Keyword(s):

Thermal Expansion ◽

Thermal Properties ◽

Bulk Modulus ◽

Elastic Constants ◽

First Principles ◽

First Principles Calculations ◽

Generalized Gradient ◽

Generalized Gradient Approximation ◽

Debye Method ◽

Good Agreement

This paper reports a study on the structure and elastic properties of cubic α-Ni4N by performing first principles calculations within Generalized gradient approximation (GGA). The calculated lattice constant and elastic constants are in good agreement with the available experimental or theoretical value. The thermal properties including the bulk modulus, thermal expansion, Grüneisen parameter and Debye temperature have also been calculated within the quasi-harmonic Debye method.

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First Principles Calculations of Magnetic Properties of LaMnO3 and La2/3 Al1/3 MnO3 Perovskite Manganites

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.754-755.766 ◽

2015 ◽

Vol 754-755 ◽

pp. 766-769

Author(s):

A. Chik ◽

S. Saad ◽

F. Che Pa ◽

C.K. Yeoh ◽

R.M. Zaki

Keyword(s):

Density Functional Theory ◽

Magnetic Properties ◽

First Principles ◽

Density Functional ◽

Magnetic Moments ◽

Perovskite Manganites ◽

First Principles Calculations ◽

Generalized Gradient ◽

Functional Theory ◽

Generalized Gradient Approximation

The magnetic properties of the perovskite manganites LaMnO3(LMO) and La2/3Al1/3MnO3(LAMO) was presented. The calculations were made within density functional theory and generalized-gradient approximation (GGA) exchange correlations energy. It was found that LAMO exhibit magnetic properties and stabilizes in antiferromagnetic structure. However cell magnetization and magnetic moments reduce with inclusion of Al dopant.

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Lattice dynamics, phonon vibrational spectra, and thermal properties of tetragonal SrPt3P: a first-principles study

RSC Advances ◽

10.1039/c5ra24600h ◽

2016 ◽

Vol 6 (32) ◽

pp. 27060-27067 ◽

Cited By ~ 2

Author(s):

Xiu-Qing Zhang ◽

Zhao-Yi Zeng ◽

Yan Cheng ◽

Guang-Fu Ji

Keyword(s):

Density Functional Theory ◽

Thermal Properties ◽

Vibrational Spectra ◽

First Principles ◽

Lattice Dynamics ◽

Density Functional ◽

Generalized Gradient ◽

Functional Theory ◽

Generalized Gradient Approximation ◽

First Principles Study

The phonon vibrational spectra and thermal properties of the platinum-based superconductor SrPt3P are investigated by the generalized gradient approximation (GGA) in the framework of density functional theory (DFT).

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STRUCTURAL, MECHANICAL AND LATTICE DYNAMICAL STABILITY OF AgC AND AuC COMPOUNDS: A FIRST PRINCIPLES STUDY

Modern Physics Letters B ◽

10.1142/s0217984912501072 ◽

2012 ◽

Vol 26 (17) ◽

pp. 1250107 ◽

Cited By ~ 2

Author(s):

ENGIN ATESER ◽

HAVVA BOGAZ OZISIK

Keyword(s):

First Principles ◽

Density Functional ◽

Phonon Dispersion ◽

Correlation Effects ◽

Generalized Gradient ◽

Functional Theory ◽

Exchange Correlation ◽

Generalized Gradient Approximation ◽

Dynamical Properties ◽

Stable Structures

Based on density functional theory, we have studied the structural stability, elastic, mechanical and lattice dynamical properties of AgC and AuC compounds for various structures: NaCl ( B1 ), CsCl ( B2 ), ZnS ( B3 ), wurtzite ( B4 ), WC ( B h), NiAs ( B8 1) and CdTe . Generalized gradient approximation has been used for modeling exchange-correlation effects. The second-order elastic constants and related polycrystalline properties (bulk modulus, shear modulus, Young's modulus, Poisson's ratio, Debye temperature and sound velocities) have been calculated and discussed. We have also calculated phonon dispersion and phonon density of states of these compounds in all considered structures. According to the results, we found that, AgC compound is mechanically and dynamically stable in B8 1, B1 and B4 structures. Our results indicate that B81 and B3 are the candidate stable structures energetically, mechanically and dynamically for AgC and AuC compounds, respectively.

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