First-principles calculations of the stability and electronic properties of the PbTiO3(110) polar surface

2009 ◽  
Vol 30 (12) ◽  
pp. 1785-1798 ◽  
Author(s):  
Guo-Xu Zhang ◽  
Ying Xie ◽  
Hai-Tao Yu ◽  
Hong-Gang Fu
Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 445
Author(s):  
Longpeng Zhu ◽  
Jiong Wang ◽  
Chenchen Dong ◽  
Yong Du ◽  
Shun-Li Shang ◽  
...  

Owing to exploring the influence of the N atoms ordering in Ta2N compounds on their properties, the stability, elastic, and electronic properties of Ta2N compounds (Ta2N-I: P3¯ml and Ta2N-II: P3¯1m) were investigated using first-principles calculations based on density functional theory. Ta2N-II is energetically favorable according to the enthalpy of formation. Elastic constants were employed to reveal the stronger resistance to deformation, but weaker anisotropy, in Ta2N-II. A ductile-brittle transition was found between Ta2N-I (ductile) and Ta2N-II (brittle). The partial density of states showed a stronger orbital hybridization of Ta-d and N-p in Ta2N-II, resulting in stronger covalent bonding. The charge density difference illustrated the interaction of the Ta-N bond and electron distribution of Ta2N.


2019 ◽  
Author(s):  
Henrik Pedersen ◽  
Björn Alling ◽  
Hans Högberg ◽  
Annop Ektarawong

Thin films of boron nitride (BN), particularly the sp<sup>2</sup>-hybridized polytypes hexagonal BN (h-BN) and rhombohedral BN (r-BN) are interesting for several electronic applications given band gaps in the UV. They are typically deposited close to thermal equilibrium by chemical vapor deposition (CVD) at temperatures and pressures in the regions 1400-1800 K and 1000-10000 Pa, respectively. In this letter, we use van der Waals corrected density functional theory and thermodynamic stability calculations to determine the stability of r-BN and compare it to that of h-BN as well as to cubic BN and wurtzitic BN. We find that r-BN is the stable sp<sup>2</sup>-hybridized phase at CVD conditions, while h-BN is metastable. Thus, our calculations suggest that thin films of h-BN must be deposited far from thermal equilibrium.


2021 ◽  
Vol 606 ◽  
pp. 412825
Author(s):  
Wei-Hong Liu ◽  
Wei Zeng ◽  
Fu-Sheng Liu ◽  
Bin Tang ◽  
Qi-Jun Liu ◽  
...  

2021 ◽  
Vol 2 (7) ◽  
pp. 2398-2407
Author(s):  
Joshua J. Brown ◽  
Youxiang Shao ◽  
Zhuofeng Ke ◽  
Alister J. Page

First-principles calculations predict the stability and mobility of vacancy defects in niobium perovskite oxynitrides, aiding defect engineering for enhanced photocatalysis.


Sign in / Sign up

Export Citation Format

Share Document