First-principles calculations of LaNi4Al–H solid solution and hydrides

0.995(Bi1/2Na1/2)TiO3-0.005Bi(B’,B”)O3 solid-solution ceramics (B’,B” denote Zn, Mg, Ni, Ti, Nb) were fabricated and their ferroelectric properties were investigated. Based on the structural characteristics of Bi(B’,B”)O3 analyzed by first-principles calculations, a materials design for obtaining a large piezoelectric strain is proposed: an index Z= Ps∙(ε33*∙s33)1/2, where Ps is spontaneous polarization, ε33* is relative permittivity and s33 is elastic compliance. A positive correlation was observed between Z and effective piezoelectric constant d33* observed for strain measurements.

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Effects of Y and Zn atoms on the elastic properties of Mg solid solution from first-principles calculations

physica status solidi (b) ◽

10.1002/pssb.201147247 ◽

2011 ◽

Vol 248 (12) ◽

pp. 2809-2815 ◽

Cited By ~ 8

Author(s):

Fang Yang ◽

Tou-Wen Fan ◽

Jian Wu ◽

Bi-Yu Tang ◽

Li-Ming Peng ◽

...

Keyword(s):

Solid Solution ◽

Elastic Properties ◽

First Principles ◽

First Principles Calculations

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Ab initio calculation of the electronic structure of a solid solution of strontium-bismuth molybdat

Journal of Physics Conference Series ◽

10.1088/1742-6596/2094/2/022043 ◽

2021 ◽

Vol 2094 (2) ◽

pp. 022043

Author(s):

E V Sokolenko ◽

E S Buyanova ◽

Z A Mikhaylovskaya ◽

G V Slusarev

Keyword(s):

Solid Solution ◽

Electronic Structure ◽

First Principles ◽

Ab Initio Calculation ◽

Structural Data ◽

Reflection Spectra ◽

First Principles Calculations ◽

X Ray ◽

Gap Width ◽

Band Gap Width

Abstract Scheelite-like compounds based on SrMoO4 have been studied. Based on X–ray structural data, models of Sr1-3xBi2xMoO4 structures (x=0.2125) are constructed, at x≧0.175, a superstructural ordering is observed associated with the location of cationic vacancies. From the first principles, calculations of the density of states in the vicinity of the forbidden zone are performed. The calculated values of the band gap width were compared with the values obtained from the reflection spectra.

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Structural Transition of Vacancy-Solute Complexes in Al-Mg-Si Alloys

Metals ◽

10.3390/met12010002 ◽

2021 ◽

Vol 12 (1) ◽

pp. 2

Author(s):

Masataka Mizuno ◽

Kazuki Sugita ◽

Hideki Araki

Keyword(s):

Solid Solution ◽

Monte Carlo ◽

Monte Carlo Simulations ◽

First Principles ◽

Structural Transition ◽

First Principles Calculations ◽

Eye Formation

To theoretically examine the structural transition of vacancy–solute complexes in Al–Mg–Si alloys, we performed first-principles calculations for layered vacancy–solute complexes with additional Mg atoms. The central Mg atom in the additional Mg layer shifted to the Si layer with the increase in the number of Mg atoms to weaken the repulsive Mg–Mg interaction and to form Mg–Si bonds. When five Mg atoms were added to the layered vacancy–solute complex, the central Mg atom completely shifted to the Si layer, and a Mg vacancy was formed in the Mg layer, which indicated that the β″-eye is formed upon the addition of Mg atoms. We reproduced β″-eye formation from a solid solution with a vacancy using first-principles-based Monte Carlo simulations. Once the β″-eye was formed on the layered vacancy–solute complex, the process can be repeated by the formation of alternate Mg and Si layers along [010] β″. These results clearly indicate that the layered vacancy–solute complex plays an important role in β″-eye formation.

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