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Structures of Amorphous Silicate Dusts Simulated by Molecular Dynamics Method

Published online by Cambridge University Press:  12 April 2016

A. Tsuchiyama  and
K. Kawamura
A. Tsuchiyama
Affiliation:
Department of Earth and Planetary Sciences, College of General Education Osaka UniversityToyonaka 560Japan
K. Kawamura
Affiliation:
Department of Earth and Planetary Sciences, College of General Education Osaka UniversityToyonaka 560Japan

Abstract

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Atomic structures of amorphous silicate dusts with the MgSiO3 composition were simulated by molecular dynamics method as a function or the dust density based on the assumption that the density corresponds to cooling rate of dust formation. The SiO4 tetrahedra are more polymerized with decreasing density, suggesting phase separation between SiO2-rich and MgO-rich components in less dense dusts formed by rapid condensation. A mode of atomic vibration probably due to the Si-0 bending is different in the amorphous silicates with different densities. This may cause changes of the 20 μm bands of IR spectra of silicate dusts with different cooling rates.

Type
Interplanetary Dust: Physical and Chemical Analysis
Information
International Astronomical Union Colloquium , Volume 126: Origin and Evolution of Interplanetary Dust , 1991 , pp. 113 - 116
Copyright
Copyright © Kluwer 1991

References

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