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Title: Structure and Stability of Small Boron and Boron Oxide Clusters

Abstract

In order to rationally design and explore a potential energy source based on the highly exothermic oxidation of boron, density functional theory (DFT) was used to characterize small boron clusters with 0-3 oxygen atoms and total of up to ten atoms. The structures, vibrational frequencies, and stabilities were calculated for each of these clusters. A quantum molecular dynamics procedure was used to locate the global minimum for each species, which proved to be crucial given the unintuitive structure of many of the most stable isomers. Additionally, due to the plane-wave, periodic DFT code used in this study, a straightforward comparison of these clusters to the bulk boron and B2O3 structures was possible, despite the great structural and energetic differences between the two forms. Through evaluation of previous computational and experimental work, the relevant low-energy structures of all but one of the pure boron clusters can be assigned with great certainty. Nearly all of the boron oxide clusters are described here for the first time, but there are strong indications that the DFT procedure chosen is particularly well-suited for the task. Insight into the trends in boron and boron oxide cluster stabilities, as well as the ultimate limits of growth formore » each, are also provided. The work reported herein provides crucial information towards understanding the oxidation of boron at a molecular level.« less

Authors:
 [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Center for Computational Sciences
Sponsoring Org.:
USDOE Laboratory Directed Research and Development (LDRD) Program
OSTI Identifier:
944596
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physical Chemistry A; Journal Volume: 111; Journal Issue: 28
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; BORON; BORON OXIDES; MOLECULAR CLUSTERS; DENSITY FUNCTIONAL METHOD; POTENTIAL ENERGY; STABILITY; ELECTRONIC STRUCTURE; VIBRATIONAL STATES; MOLECULAR DYNAMICS METHOD

Citation Formats

Sumpter, Bobby G, Drummond, Michael L, and Meunier, Vincent. Structure and Stability of Small Boron and Boron Oxide Clusters. United States: N. p., 2007. Web.
Sumpter, Bobby G, Drummond, Michael L, & Meunier, Vincent. Structure and Stability of Small Boron and Boron Oxide Clusters. United States.
Sumpter, Bobby G, Drummond, Michael L, and Meunier, Vincent. Mon . "Structure and Stability of Small Boron and Boron Oxide Clusters". United States. doi:.
@article{osti_944596,
title = {Structure and Stability of Small Boron and Boron Oxide Clusters},
author = {Sumpter, Bobby G and Drummond, Michael L and Meunier, Vincent},
abstractNote = {In order to rationally design and explore a potential energy source based on the highly exothermic oxidation of boron, density functional theory (DFT) was used to characterize small boron clusters with 0-3 oxygen atoms and total of up to ten atoms. The structures, vibrational frequencies, and stabilities were calculated for each of these clusters. A quantum molecular dynamics procedure was used to locate the global minimum for each species, which proved to be crucial given the unintuitive structure of many of the most stable isomers. Additionally, due to the plane-wave, periodic DFT code used in this study, a straightforward comparison of these clusters to the bulk boron and B2O3 structures was possible, despite the great structural and energetic differences between the two forms. Through evaluation of previous computational and experimental work, the relevant low-energy structures of all but one of the pure boron clusters can be assigned with great certainty. Nearly all of the boron oxide clusters are described here for the first time, but there are strong indications that the DFT procedure chosen is particularly well-suited for the task. Insight into the trends in boron and boron oxide cluster stabilities, as well as the ultimate limits of growth for each, are also provided. The work reported herein provides crucial information towards understanding the oxidation of boron at a molecular level.},
doi = {},
journal = {Journal of Physical Chemistry A},
number = 28,
volume = 111,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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