Structure, stability, mechanical and electronic properties of Fe–P binary compounds by first-principles calculations

RSC Advances ◽  
2015 ◽  
Vol 5 (100) ◽  
pp. 81943-81956 ◽  
Author(s):  
Jing Wu ◽  
XiaoYu Chong ◽  
Rong Zhou ◽  
YeHua Jiang ◽  
Jing Feng

The equilibrium crystal structures, stability, elastic properties, hardness and electronic structures of all the Fe–P binary compounds are investigated systematically by first principles calculations.

2020 ◽  
Vol 34 (17) ◽  
pp. 2050150
Author(s):  
Dan Hong ◽  
Wei Zeng ◽  
Fu-Sheng Liu ◽  
Bin Tang ◽  
Qi-Jun Liu

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.


2009 ◽  
Vol 1224 ◽  
Author(s):  
Yunjiang Wang ◽  
Chongyu Wang

AbstractThe effect of alloying elements Ta, Mo, W, Cr, Re, Ru, Co, and Ir on the elastic properties of both γ-Ni and γ′-Ni3Al is studied by first-principles method. Results for lattice properties, elastic moduli and the ductile/brittle behaviors are all presented. Our calculated values agree well with the existing experimental observations. Results show all the additions decrease the lattice misfit between and γ′ phases. Different alloying elements are found to have different effect on the elastic moduli of γ-Ni. Whereas all the alloying elements slightly increase the moduli of γ′-Ni3Al expect Co. Both of the two phases are becoming more brittle with alloying elements, but Co is excepted. The electronic structures of γ′ phase alloyed with different elements are provided as example to elucidate the different strengthening mechanisms.


Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1640 ◽  
Author(s):  
Yangqi Ji ◽  
Xiaoli Yuan

The elastic properties and electronic properties of MxNy (M = Ti, Zr) TiN, Ti2N, Zr3N4, ZrN with different structures have been investigated using density functional theory. Through the calculation of the elastic constants, it was found that all of these structures meet the mechanical stability except for ZrN with space group P63mc. Their mechanical properties are studied by a comparison of various parameters. The stiffness of TiN is larger than that of ZrN with space group Fm 3 ¯ m. Ti2N’s stiffness with space group I41/amdz is larger than Ti2N with space group P42/mnm. Zr3N4’s stiffness with space group Pnam is largest in three structures of Zr3N4. TiN, Ti2N and ZrN are non-central force, Zr3N4 is central force. TiN and ZrN with space group Fm 3 ¯ m are brittle, and TiN is brittler than ZrN with space group Fm 3 ¯ m. The two kinds of Ti2N are brittle and Ti2N with space group I41/amdz is larger. Three structures of Zr3N4 are tough and Zr3N4 with space group I 4 ¯ 3d is the toughest. Meanwhile, the electronic properties of TiN, Ti2N, Zr3N4 and ZrN were calculated, possible superconducting properties of the studied materials were predicted.


Applying first-principles calculations, the investigation of the geometrical and electronic properties of Pr adsorption armchair silicene nanoribbons structure has been established. The results show that the bandgap doped Pr has been changed, which is the case for chemical adsorption on the surface of ASiNRs; this material became metallic with the peak of valance band contact fermi level. Moreover, the survey to find the optimal height 1.82 Å of Pr and 2.24 Å bond length Si-Si, and Si-Si-Si bond angle 108005’, energy adsorption is -7.65 eV, buckling is 0.43 Å with structure stability close to the pristine case, has brought good results for actively creating newly applied materials for the spintronic and optoelectronics field in the future.


2015 ◽  
Vol 645-646 ◽  
pp. 325-329
Author(s):  
Jin Long Tang ◽  
Jun Nan Zhong ◽  
Cai Wen

Based on first-principles calculations, we have investigated atomic and electronic structures of 4H-SiC crystal doped by N, P and As elements as n-type dopants. We have obtained the bond lengths of the optimization system, as well as the impurity levels, the band structure and the density of states. The results show that the higher impurity level above the Fermi level is observed when 4H-SiC doped by N with concentration as 6.25% in these dopants, and the band gap of 4H-SiC decreases while the doping concentration or the atomic number of dopant increases.


Sign in / Sign up

Export Citation Format

Share Document