Numerical Study on Thermal Boundary Resistance and Conductive Properties of Cu/Al Interface

In this paper, the thermal boundary resistance and conductive properties of Cu/Al interface are investigated by using first-principles calculations based on density functional theory (DFT) with considering the pressure influence. Based on the atomic model of Cu/Al interface the simulation results show that the lattice parameters for both Cu and Al are sensitive to pressure and density states of Cu/Al interface increase as pressure increases from 0 to 5 GPa. Although Cu and Al have the same atomic structure, the significant differences of the density of phonon states lead to the thermal resistance that exists at the Cu/Al interface. At the Cu/Al interface, Cu and Al atoms can diffuse into each other and form an alloy-like interfacial region. The change of the copper component in the alloy can considerably affect the conductive properties of Cu/Al interface.

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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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Hydrogenation and oxidation enhances the thermoelectric performance of Si2BN monolayer

New Journal of Chemistry ◽

10.1039/d0nj06000c ◽

2021 ◽

Author(s):

H. R. Mahida ◽

Deobrat Singh ◽

Yogesh Sonvane ◽

Sanjeev K. Gupta ◽

P. B. Thakor ◽

...

Keyword(s):

Density Functional Theory ◽

Charge Transport ◽

Transport Properties ◽

First Principles ◽

Density Functional ◽

Thermoelectric Performance ◽

First Principles Calculations ◽

Functional Theory

In the present study, we have investigated the structural, electronic, and charge transport properties of pristine, hydrogenated, and oxidized Si2BN monolayers via first-principles calculations based on density functional theory (DFT).

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Probing the electronic structures of Con (n = 1–5) clusters on γ-Al2O3 surfaces using first-principles calculations

Physical Chemistry Chemical Physics ◽

10.1039/c6cp06785a ◽

2017 ◽

Vol 19 (5) ◽

pp. 3679-3687 ◽

Cited By ~ 10

Author(s):

Tao Yang ◽

Masahiro Ehara

Keyword(s):

Density Functional Theory ◽

First Principles ◽

Electronic Structures ◽

Density Functional ◽

Density Functional Theory Calculations ◽

First Principles Calculations ◽

Functional Theory

Using density functional theory calculations, we discussed the geometric and electronic structures and nucleation of small Co clusters on γ-Al2O3(100) and γ-Al2O3(110) surfaces.

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Electronic structure of cubic BaTbO3 from first-principles pseudopotential calculations

Canadian Journal of Physics ◽

10.1139/p06-008 ◽

2006 ◽

Vol 84 (2) ◽

pp. 115-120 ◽

Cited By ~ 3

Author(s):

G Y Gao ◽

K L Yao ◽

Z L Liu

Keyword(s):

Electronic Structure ◽

First Principles ◽

Density Functional ◽

First Principles Calculations ◽

Generalized Gradient ◽

Functional Theory ◽

Exchange Correlation ◽

Pseudopotential Calculations ◽

Correlation Potential ◽

Density Contour

First-principles calculations of the electronic structure are performed for cubic BaTbO3 using the plane-wave pseudopotential method within the framework of density functional theory and using the generalized gradient approximation for the exchange-correlation potential. Our calculations show that cubic BaTbO3 is metallic, and that this metallic character is mainly governed by the Tb 4f electrons and the hybridization between the Tb 5d and O 2p states. From the analysis of the density of states, band structure, and charge density contour, we find that the chemical bonding between Tb and O is covalent while that between Ba and TbO3 is ionic. PACS Nos.: 71.15.Mb, 71.20.-b

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Computational investigation of NH3 adsorption and dehydrogenation on a W-modified Fe(111) surface

Physical Chemistry Chemical Physics ◽

10.1039/c5cp05983f ◽

2015 ◽

Vol 17 (45) ◽

pp. 30598-30605 ◽

Cited By ~ 3

Author(s):

Ming-Kai Hsiao ◽

Chia-Hao Su ◽

Ching-Yang Liu ◽

Hui-Lung Chen

Keyword(s):

Density Functional Theory ◽

First Principles ◽

Density Functional ◽

First Principles Calculations ◽

Computational Investigation ◽

Functional Theory ◽

Nh3 Adsorption ◽

Tungsten Metal

We employed monolayer tungsten metal to modify the Fe(111) surface, denoted as W@Fe(111), and calculated the adsorption and dehydrogenation behaviors of NH3 on W@Fe(111) surface via first-principles calculations based on density functional theory (DFT).

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Magnetism and Half-Metallicity in (100) Surface of Inverse Heusler Mn2CoSb

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1015.377 ◽

2014 ◽

Vol 1015 ◽

pp. 377-380

Author(s):

Tao Chen ◽

Ying Chen ◽

Yin Zhou ◽

Hong Chen

Keyword(s):

Density Functional Theory ◽

Magnetic Properties ◽

First Principles ◽

Heusler Alloy ◽

Density Functional ◽

Magnetic Moments ◽

Surface States ◽

First Principles Calculations ◽

Half Metallicity ◽

Functional Theory

Using the first-principles calculations within density functional theory (DFT), we investigated the electronic and magnetic properties of (100) surface of inverse Heusler alloy Mn2CoSb with five different terminations. Our work reveals that the surface Mn atom moves to vacuum while surface Co atom moves to slab. Moreover, duo to the reason that the surface atom lost half of the nearest atoms with respect to the bulk phase, resulting in the decrease of hybridization, the atom-resolved spin magnetic moments of surface atoms are enhanced. Further investigation on DOS and PDOS showed that half-metallicity was preserved only in SbSb-termination while was destroyed in MnCo-, MnSb-, MnMn-, and CoCo-termination due to the appearance of surface states.

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First-principles study of static displacements in Fe-Pd magnetic shape-memory alloys

MRS Proceedings ◽

10.1557/proc-1200-g04-04 ◽

2009 ◽

Vol 1200 ◽

Cited By ~ 1

Author(s):

Markus E. Gruner

Keyword(s):

Density Functional Theory ◽

Electronic Structure ◽

First Principles ◽

Density Functional ◽

First Principles Calculations ◽

Magnetic Shape Memory ◽

Magnetic Shape Memory Alloys ◽

Functional Theory ◽

Lennard Jones ◽

Theory Comparison

AbstractThis contribution reports static ionic displacements in ferromagnetic disordered Fe70Pd30 alloys obtained by relaxation of the ionic positions of a 108-atom supercell within the framework of density functional theory. Comparison with a simple statistical model based on Lennard-Jones pair interactions reveals that these displacements are significantly larger than can be explained by the different sizes of the elemental constituents. The discrepancies are presumably related to collective displacements of the Fe atoms. Corresponding distortions are experimentally observed for ordered Fe3Pt and predicted by first-principles calculations for all ordered Fe-rich L12 alloys with Ni group elements and originate from details of the electronic structure at the Fermi level.

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Electronic, optical and thermoelectric properties of Fe2ZrP compound determined via first-principles calculations

RSC Advances ◽

10.1039/c9ra04736k ◽

2019 ◽

Vol 9 (44) ◽

pp. 25900-25911 ◽

Cited By ~ 3

Author(s):

Esmaeil Pakizeh ◽

Jaafar Jalilian ◽

Mahnaz Mohammadi

Keyword(s):

Density Functional Theory ◽

Thermoelectric Properties ◽

First Principles ◽

Density Functional ◽

Transport Theory ◽

First Principles Calculations ◽

Boltzmann Transport ◽

Functional Theory ◽

Boltzmann Transport Theory ◽

The Density Functional Theory

In this study, based on the density functional theory and semi-classical Boltzmann transport theory, we investigated the structural, thermoelectric, optical and phononic properties of the Fe2ZrP compound.

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First principles calculations on theoretical band gap improvement of IIIA-VA zinc-blende semiconductor InAs

International Journal of Modern Physics C ◽

10.1142/s0129183120501788 ◽

2020 ◽

Vol 31 (12) ◽

pp. 2050178

Author(s):

Waqas Mahmood ◽

Arfan Bukhtiar ◽

Muhammad Haroon ◽

Bing Dong

Keyword(s):

Band Gap ◽

Density Functional ◽

Local Density ◽

Lattice Parameter ◽

First Principles Calculations ◽

Functional Theory ◽

Zinc Blende ◽

Valence States ◽

Direct Band ◽

Experimental Findings

The structural, electronic, dielectric and vibrational properties of zinc-blende (ZB) InAs were studied within the framework of density functional theory (DFT) by employing local density approximation and norm-conserving pseudopotentials. The optimal lattice parameter, direct band gap, static dielectric constant, phonon frequencies and Born effective charges calculated by treating In-4d electrons as valence states are in satisfactory agreement with other reported theoretical and experimental findings. The calculated band gap is reasonably accurate and improved in comparison to other findings. This work will be useful for more computational studies related to semiconductor devices.

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Effect of Defects on Spontaneous Polarization in Pure and Doped LiNbO3: First-Principles Calculations

Materials ◽

10.3390/ma12010100 ◽

2018 ◽

Vol 12 (1) ◽

pp. 100 ◽

Cited By ~ 5

Author(s):

Weiwei Wang ◽

Dahuai Zheng ◽

Mengyuan Hu ◽

Shahzad Saeed ◽

Hongde Liu ◽

...

Keyword(s):

Spontaneous Polarization ◽

First Principles ◽

Density Functional ◽

Lattice Distortion ◽

Stable Structure ◽

First Principles Calculations ◽

Functional Theory ◽

The Density Functional Theory ◽

Specific Configuration ◽

The Relationship

Numerous studies have indicated that intrinsic defects in lithium niobate (LN) dominate its physical properties. In an Nb-rich environment, the structure that consists of a niobium anti-site with four lithium vacancies is considered the most stable structure. Based on the density functional theory (DFT), the specific configuration of the four lithium vacancies of LN were explored. The results indicated the most stable structure consisted of two lithium vacancies as the first neighbors and the other two as the second nearest neighbors of Nb anti-site in pure LN, and a similar stable structure was found in the doped LN. We found that the defects dipole moment has no direct contribution to the crystal polarization. Spontaneous polarization is more likely due to the lattice distortion of the crystal. This was verified in the defects structure of Mg2+, Sc3+, and Zr4+ doped LN. The conclusion provides a new understanding about the relationship between defect clusters and crystal polarization.

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