The structural, elastic and electronic properties of A2C2 (A = Li, Na, K, Rb and Cs): First-principles calculations

The structural, elastic and electronic properties of A2 C 2 (A = Li , Na , K , Rb and Cs ) at zero temperature were investigated by first-principles total energy calculations. The optimized equilibrium structural parameters agree well with available experimental values. Elastic constants, bulk modulus, Young's modulus and Poissons ratio were given. All the structures studied are stable mechanically and all stable A2 C 2 studied has strong compressibility, which originates from weak Coulomb repulsion between metal atoms and carbon atoms. The electronic structure calculations show that binary alkali metal carbides studied here are insulators.

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First principles study of structure, electronic and optical properties of Y3Fe5O12 in cubic and trigonal phases

Materials Science-Poland ◽

10.1515/msp-2015-0015 ◽

2015 ◽

Vol 33 (1) ◽

pp. 169-174 ◽

Cited By ~ 4

Author(s):

Shen Tao ◽

Hu Chao ◽

Dai Hailong ◽

Yang Wenlong ◽

Liu Hongchen ◽

...

Keyword(s):

Refractive Index ◽

Optical Properties ◽

Energy Loss ◽

First Principles ◽

Structural Parameters ◽

Band Gaps ◽

First Principles Calculations ◽

Electronic And Optical Properties ◽

Direct Band ◽

Experimental Values

AbstractFirst principles calculations have been performed to investigate the structure, electronic and optical properties of Y3Fe5O12. Both the cubic and trigonal phases have been considered in our calculation. The calculated structural parameters are slightly larger than the experimental values. The band structures show that Y3Fe5O12 in cubic and trigonal phases have direct band gaps of 0.65 and 0.17 eV. The calculations of dielectric function, absorption, extinction coefficient, refractive index, energy loss function and reflectivity are presented.

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Mechanical and electronic properties of Ti-7333 alloy under tension: First-principles calculations

International Journal of Modern Physics B ◽

10.1142/s0217979220501507 ◽

2020 ◽

Vol 34 (17) ◽

pp. 2050150

Author(s):

Dan Hong ◽

Wei Zeng ◽

Fu-Sheng Liu ◽

Bin Tang ◽

Qi-Jun Liu

Keyword(s):

Tensile Strength ◽

Electronic Properties ◽

Elastic Properties ◽

First Principles ◽

Structural Parameters ◽

Tension Stress ◽

Mechanical Parameters ◽

First Principles Calculations ◽

Anisotropic Behavior ◽

Resistance To Deformation

The first-principles calculations are used to investigate the effects on mechanical and electronic properties of Ti-7333 alloy under the tension stress along [001], [100] and [110] directions. First, we study the structure and elastic properties of Ti-7333 alloy with 2, 16, 54 and 128 atoms, finding that the structural parameters of four models are comparative due to the approximate value of c/a and the elastic properties are also similar. Hence, we choose Ti-7333 alloy with 16 atoms to study the effects on mechanical and electronic properties under tension stress along [001], [100] and [110] directions. The changes of independent elastic constants, Debye temperature and anisotropic behavior under different tension stress along all the three directions can reflect that the tensile strength of Ti-7333 alloy may exist between [Formula: see text] and [Formula: see text] GPa and also find that it is easier to change the resistance to deformation of Ti-7333 alloy under the tension stress along [100] direction compared with [001] and [110] directions. What’s more, the calculated mechanical parameters show that the Ti-7333 alloy is brittle and the tendency of variations is small with the increase in tension stress. The effects on electronic properties including metallic and covalent properties are not obvious due to the approximate height of TDOS, pseudogap and charge density.

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Structural, elastic and electronic properties of transition metal carbides TMC (TM=Ti, Zr, Hf and Ta) from first-principles calculations

Solid State Communications ◽

10.1016/j.ssc.2011.02.005 ◽

2011 ◽

Vol 151 (8) ◽

pp. 602-606 ◽

Cited By ~ 54

Author(s):

Hui Li ◽

Litong Zhang ◽

Qingfeng Zeng ◽

Kang Guan ◽

Kaiyuan Li ◽

...

Keyword(s):

Transition Metal ◽

Electronic Properties ◽

First Principles ◽

First Principles Calculations ◽

Metal Carbides ◽

Transition Metal Carbides

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Mechanical and Electronic Properties of P42/mnm Silicon Carbides

Zeitschrift für Naturforschung A ◽

10.1515/zna-2015-0539 ◽

2016 ◽

Vol 71 (5) ◽

pp. 387-396 ◽

Cited By ~ 9

Author(s):

Quan Zhang ◽

Qun Wei ◽

Haiyan Yan ◽

Qingyang Fan ◽

Xuanmin Zhu ◽

...

Keyword(s):

Density Functional Theory ◽

Electronic Structure ◽

Electronic Properties ◽

First Principles ◽

Density Functional ◽

Electronic Structure Calculations ◽

First Principles Calculations ◽

Functional Theory ◽

Silicon Carbides ◽

Structure Calculations

AbstractTwo new phases of Si8C4 and Si4C8 with the P42/mnm symmetry are proposed. Using first principles calculations based on density functional theory, the structural, elastic, and electronic properties of Si8C4 and Si4C8 are studied systematically. Both Si8C4 and Si4C8 are proved to be mechanically and dynamically stable. The elastic anisotropies of Si8C4 and Si4C8 are studied in detail. Electronic structure calculations show that Si8C4 and Si4C8 are indirect semiconductors with the band gap of 0.74 and 0.15 eV, respectively.

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Elastic Properties and Electronic Structures of L12-TiAl3 and L12-Ti(Al,Pt)3: A Density Functional Theory Investigation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.817.816 ◽

2015 ◽

Vol 817 ◽

pp. 816-825

Author(s):

Bo Huang ◽

Yong Hua Duan ◽

Sun Yong ◽

Ming Jun Peng

Keyword(s):

Elastic Properties ◽

First Principles ◽

Electronic Structures ◽

Density Functional ◽

Structural Parameters ◽

First Principles Calculations ◽

Elastic Parameters ◽

Electronic Density ◽

Functional Theory ◽

Experimental Values

First-principles calculations have been carried out to investigate the elastic properties and electronic structures of L12-TiAl3and L12-Ti (Al, Pt)3. The optimized structural parameters were largely consistent with the experimental values. The electronic density of states (DOS) and the differences of charge density distribution were given. The independent single-crystal elastic constants and polycrystalline elastic parameters such as bulk modulusB, Young’s modulusE, shear modulusG, Poisson’s ratioνand anisotropy valueAhave been calculated by Voigt-Reuss-Hill averaging scheme. The results indicate that the L12-Ti (Al, Pt)3exhibits larger anisotropy and more ductile than L12-TiAl3.

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