Lattice Thermal Transport in Monolayer Group 13 Monochalcogenides MX (M = Ga, In; X = S, Se, Te): Interplay of Atomic Mass, Harmonicity, and Lone-Pair-Induced Anharmonicity

As3+ cation possessing stereochemically active lone pairs (SALP), leads to high SHG coefficients of nonlinear-optic crystal LiAsS2, but the role of SALP in determining thermal transport behavior of LiAsS2 is...

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Advances in computational studies of energy materials

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2010.0111 ◽

2010 ◽

Vol 368 (1923) ◽

pp. 3379-3456 ◽

Cited By ~ 96

Author(s):

C. R. A. Catlow ◽

Z. X. Guo ◽

M. Miskufova ◽

S. A. Shevlin ◽

A. G. H. Smith ◽

...

Keyword(s):

Interatomic Potential ◽

Computational Modelling ◽

Lone Pair ◽

Energy Storage And Conversion ◽

Energy Materials ◽

Group 13 ◽

Energy Technologies ◽

Nanostructured Systems ◽

Recent Developments ◽

Modelling Techniques

We review recent developments and applications of computational modelling techniques in the field of materials for energy technologies including hydrogen production and storage, energy storage and conversion, and light absorption and emission. In addition, we present new work on an Sn 2 TiO 4 photocatalyst containing an Sn(II) lone pair, new interatomic potential models for SrTiO 3 and GaN, an exploration of defects in the kesterite/stannite-structured solar cell absorber Cu 2 ZnSnS 4 , and report details of the incorporation of hydrogen into Ag 2 O and Cu 2 O. Special attention is paid to the modelling of nanostructured systems, including ceria (CeO 2 , mixed Ce x O y and Ce 2 O 3 ) and group 13 sesquioxides. We consider applications based on both interatomic potential and electronic structure methodologies; and we illustrate the increasingly quantitative and predictive nature of modelling in this field.

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Lattice Thermal Transport of homogeneous Cage‐Like Compounds Cu3VSe4 and Cu3NbSe4: Interplay of the Phonon Phase Space, Anharmonicity, and Atomic Mass

ChemPhysChem ◽

10.1002/cphc.202100516 ◽

2021 ◽

Author(s):

Dingfeng Yang ◽

Junzhu Yang ◽

Xuejun Quan ◽

Bin Zhang ◽

Guoyu Wang ◽

...

Keyword(s):

Phase Space ◽

Thermal Transport ◽

Atomic Mass

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The Effect of Interstitial Layers on Thermal Boundary Conductance Between Lennard-Jones Crystals

2010 14th International Heat Transfer Conference, Volume 6 ◽

10.1115/ihtc14-22953 ◽

2010 ◽

Cited By ~ 1

Author(s):

Timothy S. English ◽

John C. Duda ◽

Donald A. Jordan ◽

Pamela M. Norris ◽

Leonid V. Zhigilei

Keyword(s):

Thermal Transport ◽

Thermal Flux ◽

Atomic Mass ◽

Interfacial Transport ◽

Average Mass ◽

Thermal Boundary Conductance ◽

Lennard Jones ◽

Steady State Temperature ◽

Non Equilibrium Molecular Dynamics ◽

Dynamics Simulations

Thermal transport at the interface between Lennard-Jones crystals is explored via non-equilibrium molecular dynamics simulations. The vibrational properties of each crystal are varied by changing the atomic mass of the crystal. By applying a constant thermal flux across the two-crystal composite system, a steady-state temperature gradient is established and thermal boundary conductance at the interface between the crystals is calculated via Fourier’s law. With the material properties of the two crystals fixed, thermal boundary conductance can be affected by an intermediate layer inserted between the two crystals. It is found that when the interstitial layer atomic mass is between those values of the crystals comprising the interface, interfacial transport is enhanced. This layer helps bridge the gap between the different vibrational spectra of the two materials, thus enhancing thermal transport, which is maximized when the interstitial layer atomic mass approaches the average mass of the two fixed crystals. The degree of enhancement depends on the vibrational mismatch between the interstitial layer and the crystals comprising the interface, and we report an increase in thermal boundary conductance of up to 50%.

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Effects of Ion Beam Milling on Surface Topography

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070862 ◽

1973 ◽

Vol 31 ◽

pp. 84-85

Author(s):

P.G. Pawar ◽

P. Duhamel ◽

G.W. Monk

Keyword(s):

Surface Topography ◽

Ion Beam ◽

Solid Material ◽

Beam Current ◽

Atomic Mass ◽

Micro Milling ◽

Ion Milling ◽

Controlled Atmospheres ◽

Milling Operations ◽

Sufficient Energy

A beam of ions of mass greater than a few atomic mass units and with sufficient energy can remove atoms from the surface of a solid material at a useful rate. A system used to achieve this purpose under controlled atmospheres is called an ion miliing machine. An ion milling apparatus presently available as IMMI-III with a IMMIAC was used in this investigation. Unless otherwise stated, all the micro milling operations were done with Ar+ at 6kv using a beam current of 100 μA for each of the two guns, with a specimen tilt of 15° from the horizontal plane.It is fairly well established that ion bombardment of the surface of homogeneous materials can produce surface topography which resembles geological erosional features.

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Interlayer mixing in GaAs/AlxGa1-xAs heterostructures as a result of Se+ ion implantation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100106600 ◽

1988 ◽

Vol 46 ◽

pp. 908-909

Author(s):

E.G. Bithell ◽

W.M. Stobbs

Keyword(s):

Ion Implantation ◽

Diffusion Coefficients ◽

Dark Field ◽

Atomic Mass ◽

Composition Profile ◽

Semiconductor Heterostructures ◽

Transmission Electron ◽

Microscope Images ◽

Damage Process ◽

Electron Energy Loss

It is well known that the microstructural consequences of the ion implantation of semiconductor heterostructures can be severe: amorphisation of the damaged region is possible, and layer intermixing can result both from the original damage process and from the enhancement of the diffusion coefficients for the constituents of the original composition profile. A very large number of variables are involved (the atomic mass of the target, the mass and energy of the implant species, the flux and the total dose, the substrate temperature etc.) so that experimental data are needed despite the existence of relatively well developed models for the implantation process. A major difficulty is that conventional techniques (e.g. electron energy loss spectroscopy) have inadequate resolution for the quantification of any changes in the composition profile of fine scale multilayers. However we have demonstrated that the measurement of 002 dark field intensities in transmission electron microscope images of GaAs / AlxGa1_xAs heterostructures can allow the measurement of the local Al / Ga ratio.

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