Insights into Bulk Properties and Transport Mechanisms in New Ternary Halide Solid Electrolytes: First-Principles Calculations

The first-principles calculations of band gaps and bulk moduli of cesium lead halide perovskite solid solutions, [Formula: see text] and [Formula: see text], are performed at the level of general gradient approximation of the density functional theory. We use supercell approach for computational modeling of disordered systems, which gives a description of the properties of the structure baasing on the average over a set of multiple configurations, namely distributions of different species over a given set of atomic positions. The calculations were performed with the CRYSTAL14 program package. The dependence of the band gap and bulk modulus on the content [Formula: see text] are investigated over the whole range [Formula: see text].

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First Principles Calculations on Electron Conduction Paths in Solid Electrolytes: Toward an Understanding of the Working Mechanism of Atomic Switches

Journal of the Japan Institute of Metals and Materials ◽

10.2320/jinstmet.73.577 ◽

2009 ◽

Vol 73 (8) ◽

pp. 577-582

Author(s):

S. Watanabe ◽

T. K. Gu ◽

Z. C. Wang ◽

T. Tada

Keyword(s):

First Principles ◽

Solid Electrolytes ◽

First Principles Calculations ◽

Working Mechanism ◽

Electron Conduction

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Electronic Structure and X-ray Absorption Spectra of Rutile TiO2 Using First-Principles Calculations

Korean Journal of Metals and Materials ◽

10.3365/kjmm.2014.52.12.1025 ◽

2014 ◽

Vol 52 (12) ◽

pp. 1025-1029

Author(s):

Min-Wook Oh ◽

Tae-Gu Kang ◽

Byungki Ryu ◽

Ji Eun Lee ◽

Sung-Jae Joo ◽

...

Keyword(s):

Electronic Structure ◽

Absorption Spectra ◽

First Principles ◽

First Principles Calculations ◽

Rutile Tio2 ◽

X Ray ◽

X Ray Absorption

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To Bend or Not to Bend, the Dilemma of Multiple Bonds

10.26434/chemrxiv.8066747.v1 ◽

2019 ◽

Author(s):

Michele Pizzocchero ◽

Matteo Bonfanti ◽

Rocco Martinazzo

Keyword(s):

First Principles ◽

2D Materials ◽

Main Group ◽

First Principles Calculations ◽

Group 14 ◽

Multiple Bonds ◽

Main Group Elements ◽

Structural Distortions

The manuscript addresses the issue of the structural distortions occurring at multiple bonds between high main group elements, focusing on group 14. These distortions are known as trans-bending in silenes, disilenes and higher group analogues, and buckling in 2D materials likes silicene and germanene. A simple but correlated \sigma + \pi model is developed and validated with first-principles calculations, and used to explain the different behaviour of second- and higher- row elements.

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Thermodynamic Stability of Hexagonal and Rhombohedral Bn at Cvd Conditions from Van der Waals Corrected First Principles Calculations

10.26434/chemrxiv.8052218.v3 ◽

2019 ◽

Author(s):

Henrik Pedersen ◽

Björn Alling ◽

Hans Högberg ◽

Annop Ektarawong

Keyword(s):

Thin Films ◽

Thermodynamic Stability ◽

First Principles ◽

Thermal Equilibrium ◽

Density Functional ◽

Van Der Waals ◽

Chemical Vapor ◽

First Principles Calculations ◽

Functional Theory ◽

The Stability

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.

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