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Title: Interplay between the structure and dynamics in liquid and undercooled boron: An ab initio molecular dynamics simulation study

Abstract

In the present work, the structural and dynamic properties of liquid and undercooled boron are investigated by means of ab initio molecular dynamics simulation. Our results show that both liquid and undercooled states present a well pronounced short-range order (SRO) mainly due to the formation of inverted umbrella structural units. Moreover, we observe the development of a medium-range order (MRO) in the undercooling regime related to the increase of inverted umbrella structural units and of their interconnection as the temperature decreases. We also evidence that this MRO leads to a partial crystallization in the β-rhombohedral crystal below T = 1900 K. Finally, we discuss the role played by the SRO and MRO in the nearly Arrhenius evolution of the diffusion and the non-Arrhenius temperature dependence of the shear viscosity, in agreement with the experiment.

Authors:
;  [1]
  1. Sciences et Ingénierie des Matériaux et Procédés, UMR CNRS 5266, Grenoble INP, BP 75, 38402 Saint-Martin d’Hères Cedex (France)
Publication Date:
OSTI Identifier:
22413344
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 141; Journal Issue: 23; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; BORON; CRYSTALLIZATION; CRYSTALS; DIFFUSION; LEAD; LIQUIDS; MOLECULAR DYNAMICS METHOD; SHEAR; SIMULATION; STRONTIUM OXIDES; SUBCOOLING; TEMPERATURE DEPENDENCE; TRIGONAL LATTICES; VISCOSITY

Citation Formats

Jakse, N., and Pasturel, A. Interplay between the structure and dynamics in liquid and undercooled boron: An ab initio molecular dynamics simulation study. United States: N. p., 2014. Web. doi:10.1063/1.4903452.
Jakse, N., & Pasturel, A. Interplay between the structure and dynamics in liquid and undercooled boron: An ab initio molecular dynamics simulation study. United States. doi:10.1063/1.4903452.
Jakse, N., and Pasturel, A. Sun . "Interplay between the structure and dynamics in liquid and undercooled boron: An ab initio molecular dynamics simulation study". United States. doi:10.1063/1.4903452.
@article{osti_22413344,
title = {Interplay between the structure and dynamics in liquid and undercooled boron: An ab initio molecular dynamics simulation study},
author = {Jakse, N. and Pasturel, A.},
abstractNote = {In the present work, the structural and dynamic properties of liquid and undercooled boron are investigated by means of ab initio molecular dynamics simulation. Our results show that both liquid and undercooled states present a well pronounced short-range order (SRO) mainly due to the formation of inverted umbrella structural units. Moreover, we observe the development of a medium-range order (MRO) in the undercooling regime related to the increase of inverted umbrella structural units and of their interconnection as the temperature decreases. We also evidence that this MRO leads to a partial crystallization in the β-rhombohedral crystal below T = 1900 K. Finally, we discuss the role played by the SRO and MRO in the nearly Arrhenius evolution of the diffusion and the non-Arrhenius temperature dependence of the shear viscosity, in agreement with the experiment.},
doi = {10.1063/1.4903452},
journal = {Journal of Chemical Physics},
number = 23,
volume = 141,
place = {United States},
year = {Sun Dec 21 00:00:00 EST 2014},
month = {Sun Dec 21 00:00:00 EST 2014}
}
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