Lattice Thermal Conductivity of MgSiO
            3
            Postperovskite Under the Lowermost Mantle Conditions From Ab Initio Anharmonic Lattice Dynamics

Abstract A solid with larger sound speeds usually exhibits higher lattice thermal conductivity. Here, we report an exception that CuP2 has a quite large mean sound speed of 4155 m s−1, comparable to GaAs, but single crystals show very low lattice thermal conductivity of about 4 W m−1 K−1 at room temperature, one order of magnitude smaller than GaAs. To understand such a puzzling thermal transport behavior, we have thoroughly investigated the atomic structures and lattice dynamics by combining neutron scattering techniques with first-principles simulations. This compound crystallizes in a layered structure where Cu atoms forming dimers are sandwiched in between P atomic networks. In this work, we reveal that Cu atomic dimers vibrate as a rattling mode with frequency around 11 meV, which is manifested to be remarkably anharmonic and strongly scatters acoustic phonons to achieve the low lattice thermal conductivity.

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Effect of the electropositive elements A = Sc, La, and Ce on the microscopic dynamics of AV2Al20

Physical Chemistry Chemical Physics ◽

10.1039/c4cp04097j ◽

2014 ◽

Vol 16 (48) ◽

pp. 27119-27133 ◽

Cited By ~ 18

Author(s):

Michael Marek Koza ◽

Andreas Leithe-Jasper ◽

Erik Sischka ◽

Walter Schnelle ◽

Horst Borrmann ◽

...

Keyword(s):

Thermal Conductivity ◽

Ab Initio ◽

Ground State ◽

Lattice Thermal Conductivity ◽

Neutron Spectroscopy ◽

Cage Compound ◽

Ground State Properties ◽

Phonon Renormalization ◽

Microscopic Dynamics

Neutron spectroscopy andab initiocalculations indicate the apparent glass-like lattice thermal conductivityκlof the nano-cage compound ScV2Al20as an effect of phonon renormalization predetermined by the crystal’s ground state properties.

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Lattice dynamics and lattice thermal conductivity of thorium dicarbide

Journal of Nuclear Materials ◽

10.1016/j.jnucmat.2014.07.060 ◽

2014 ◽

Vol 454 (1-3) ◽

pp. 142-148 ◽

Cited By ~ 7

Author(s):

Zongmeng Liao ◽

Ping Huai ◽

Wujie Qiu ◽

Xuezhi Ke ◽

Wenqing Zhang ◽

...

Keyword(s):

Thermal Conductivity ◽

Lattice Dynamics ◽

Lattice Thermal Conductivity

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Critically Assessing the Application of Quantum Corrections to Classical Thermal Conductivity Predictions

Volume 2: Theory and Fundamental Research; Aerospace Heat Transfer; Gas Turbine Heat Transfer; Computational Heat Transfer ◽

10.1115/ht2009-88129 ◽

2009 ◽

Author(s):

J. E. Turney ◽

A. J. H. McGaughey ◽

C. H. Amon

Keyword(s):

Thermal Conductivity ◽

Lattice Dynamics ◽

Md Simulation ◽

Ad Hoc ◽

Quantum Systems ◽

Quantum Corrections ◽

Quantum Mechanical Treatment ◽

Anharmonic Lattice ◽

Total Energies ◽

Full Quantum

Quantum corrections can be used to map the thermal conductivity predicted in a classical framework [e.g., a molecular dynamics (MD) simulation] to a corresponding value in a quantum system. This procedure is accomplished by equating the total energies and energy fluxes of the classical and quantum systems. The validity of these corrections is questionable because they are introduced in an ad hoc manner and are not derived from first principles. In this work, the validity of these quantum corrections is examined by comparing the thermal conductivity of Stillinger-Weber silicon calculated using a full quantum mechanical treatment to a quantum-corrected value predicted from a classical framework between temperatures of 10 K and 1000 K. The quantum and classical predictions are obtained using anharmonic lattice dynamics calculations. We find discrepancies between the quantum-corrected predictions and the quantum predictions obtained directly. We investigate the causes of these discrepancies and from our findings, conclude that quantum thermal conductivities cannot be predicted by applying simple corrections to the values obtained from a purely classical framework.

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Lattice Dynamics of Graphene Nanoribbons under Twisting

Physical Chemistry Chemical Physics ◽

10.1039/d1cp03806k ◽

2021 ◽

Author(s):

Zhao Liu ◽

Zhen Zhang ◽

Hui-Yan Zhao ◽

Jing Wang ◽

Ying Liu

Keyword(s):

Thermal Conductivity ◽

Lattice Dynamics ◽

Density Functional ◽

Lattice Thermal Conductivity ◽

Graphene Nanoribbons ◽

Tight Binding ◽

Tight Binding Method ◽

Twisted Graphene

In this communication, we investigate the lattice dynamics of twisted graphene nanoribbons utilizing the density-functional tight-binding method based on screw symmetry and report the reduced lattice thermal conductivity due to...

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