First-principles calculations of phonon transport across a vacuum gap

The transmissions as functions of energy are central for electron or phonon transport in the Landauer transport picture. We suggest a simple and computationally “cheap” post-processing scheme to interpolate transmission functions over k-points to get smooth well-converged average transmission functions. This is relevant for data obtained using typical “expensive” first principles calculations where the leads/electrodes are described by periodic boundary conditions. We show examples of transport in graphene structures where a speed-up of an order of magnitude is easily obtained.

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Potential thermoelectric materials CsMI3 (M = Sn and Pb) in perovskite structures from first-principles calculations

RSC Advances ◽

10.1039/c6ra14144g ◽

2016 ◽

Vol 6 (103) ◽

pp. 101552-101559 ◽

Cited By ~ 17

Author(s):

San-Dong Guo ◽

Jian-Li Wang

Keyword(s):

Thermoelectric Properties ◽

Thermoelectric Materials ◽

First Principles ◽

Transport Theory ◽

Phonon Transport ◽

First Principles Calculations ◽

Boltzmann Transport ◽

Boltzmann Transport Theory ◽

Halide Perovskites

The thermoelectric properties of halide perovskites CsMI3 (M = Sn and Pb) are investigated from a combination of first-principles calculations and semiclassical Boltzmann transport theory by considering both the electron and phonon transport.

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First-principles calculations of phonon transport in two-dimensional penta-X2C family

Journal of Applied Physics ◽

10.1063/5.0004904 ◽

2020 ◽

Vol 127 (20) ◽

pp. 205106

Author(s):

Xin Liu ◽

Tao Ouyang ◽

Dingbo Zhang ◽

Haifeng Huang ◽

Hui Wang ◽

...

Keyword(s):

First Principles ◽

Phonon Transport ◽

Two Dimensional ◽

First Principles Calculations

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Phonon transport properties of bulk and monolayer GaN from first-principles calculations

Computational Materials Science ◽

10.1016/j.commatsci.2017.07.012 ◽

2017 ◽

Vol 138 ◽

pp. 419-425 ◽

Cited By ~ 11

Author(s):

Yongqiang Jiang ◽

Shuang Cai ◽

Yi Tao ◽

Zhiyong Wei ◽

Kedong Bi ◽

...

Keyword(s):

Transport Properties ◽

First Principles ◽

Phonon Transport ◽

First Principles Calculations

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Simulation of Phonon Transmission Through Graphene With a Green’s Function Method

Volume 12: Micro and Nano Systems, Parts A and B ◽

10.1115/imece2009-10651 ◽

2009 ◽

Author(s):

Zhen Huang ◽

Timothy Fisher ◽

Jayathi Murthy

Keyword(s):

Green’S Function ◽

Green's Function ◽

First Principles ◽

Nearest Neighbor ◽

Thermal Conductance ◽

Transmission Function ◽

Phonon Transport ◽

Future Research ◽

First Principles Calculations ◽

Best Fit

In this paper, phonon transmission through a graphene sheet is investigated using an atomistic Green’s function (AGF) method. Reported best-fit results from first-principles calculations using a 4th nearest neighbor force-constant (4NNFC) model are used to establish the matrices that describe the interactions among carbon atoms. Calculations reveal that graphene dispersion curves so obtained are in good agreement with experiments as well as other published first-principles calculations. The effect of carbon isotopes on thermal conductance is investigated, and the results reveal that isotopic doping moderately reduces both phonon transmission function and thermal conductance. The phonon transmission function of each vibrational branch in the heterogeneous interface is also calculated based on a method described in recent work, and comparisons indicate the major and minor channels of phonon transport through graphene. The results herein offer a useful reference and suggest directions for future research on thermal applications of this material.

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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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