Performance of a Parallel Molecular Dynamics Program for Computation of Thermal Properties

Yttrium Aluminum Garnet (YAG, Y3Al5O12) and its varieties have applications in thermographic phosphors, lasing mediums, and thermal barriers. In this work, thermal properties of crystalline YAG where aluminum atoms are substituted with gallium atoms (Y3(Al1−xGax)5O12) are explored with molecular dynamics simulations. For YAG at 300K, the simulations gave values close to experimental values for constant-pressure specific heat, thermal expansion, and bulk thermal conductivity. For various values of x, the simulations predicted no change in thermal expansion, an increase in specific heat, and a decrease in thermal conductivity for x = 50%. Furthermore, the simulations predicted a decrease in thermal conductivity with decreasing system size.

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Parallel molecular dynamics simulation of commercial surfactants

High-Performance Computing and Networking - Lecture Notes in Computer Science ◽

10.1007/bfb0020376 ◽

2005 ◽

pp. 223-225

Author(s):

Eamonn O'Toole ◽

Mike Surridge ◽

Colin Upstill

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulation ◽

Dynamics Simulation ◽

Parallel Molecular Dynamics

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First-Principles-Based Interatomic Potential for SI and Its Thermal Conductivity

ASME/JSME 2011 8th Thermal Engineering Joint Conference ◽

10.1115/ajtec2011-44339 ◽

2011 ◽

Author(s):

Keivan Esfarjani ◽

Gang Chen ◽

Asegun Henry

Keyword(s):

Thermal Conductivity ◽

Molecular Dynamics ◽

Thermal Properties ◽

Force Field ◽

Molecular Dynamics Simulations ◽

First Principles ◽

Density Functional ◽

Interatomic Potential ◽

Force Constants ◽

Dynamics Simulations

Based on first-principles density-functional calculations, we have developed and tested a force-field for silicon, which can be used for molecular dynamics simulations and the calculation of its thermal properties. This force field uses the exact Taylor expansion of the total energy about the equilibrium positions up to 4th order. In this sense, it becomes systematically exact for small enough displacements, and can reproduce the thermodynamic properties of Si with high fidelity. Having the harmonic force constants, one can easily calculate the phonon spectrum of this system. The cubic force constants, on the other hand, will allow us to compute phonon lifetimes and scattering rates. Results on equilibrium Green-Kubo molecular dynamics simulations of thermal conductivity as well as an alternative calculation of the latter based on the relaxation-time approximation will be reported. The accuracy and ease of computation of the lattice thermal conductivity using these methods will be compared. This approach paves the way for the construction of accurate bulk interatomic potentials database, from which lattice dynamics and thermal properties can be calculated and used in larger scale simulation methods such as Monte Carlo.

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Parallel Molecular Dynamics Code Validation Through Bulk Silicon Thermal Conductivity Calculations

Electronic and Photonic Packaging, Electrical Systems and Photonic Design, and Nanotechnology ◽

10.1115/imece2003-42352 ◽

2003 ◽

Cited By ~ 4

Author(s):

Carlos J. Gomes ◽

Marcela Madrid ◽

Cristina H. Amon

Keyword(s):

Thermal Conductivity ◽

Molecular Dynamics ◽

Single Crystals ◽

Phonon Frequency ◽

Interatomic Potential ◽

Dispersion Relations ◽

Bulk Silicon ◽

Ghost Cell ◽

Frequency Spectra ◽

Parallel Molecular Dynamics

We have implemented a parallel molecular dynamics algorithm, which incorporates the Stillinger-Weber interatomic potential. The code was parallelized using a ghost cell atomic division approach, ensuring scaling with the number of processors and a significant increase in speed with respect to the serial version. The methodology is validated by computing the thermal conductivity and phonon frequency spectra of bulk silicon single crystals for different domain sizes at 1000K. The predicted thermal conductivities are consistent with the experimental value at that temperature. In addition, the phonon frequency spectra capture the properties expected from the dispersion relations for silicon.

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