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Title: Theory and modelling of nanocarbon phase stability.

Abstract

The transformation of nanodiamonds into carbon-onions (and vice versa) has been observed experimentally and has been modeled computationally at various levels of sophistication. Also, several analytical theories have been derived to describe the size, temperature and pressure dependence of this phase transition. However, in most cases a pure carbon-onion or nanodiamond is not the final product. More often than not an intermediary is formed, known as a bucky-diamond, with a diamond-like core encased in an onion-like shell. This has prompted a number of studies investigating the relative stability of nanodiamonds, bucky-diamonds, carbon-onions and fullerenes, in various size regimes. Presented here is a review outlining results of numerous theoretical studies examining the phase diagrams and phase stability of carbon nanoparticles, to clarify the complicated relationship between fullerenic and diamond structures at the nanoscale.

Authors:
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
979539
Report Number(s):
ANL/MSD/CP-53490
TRN: US201010%%659
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Conference
Resource Relation:
Journal Name: Diamond Related Mater.; Journal Volume: 15; Journal Issue: 2-3 ; 2006; Conference: 8th International Conference on Applications of Diamond and Related Materials and 1st NanoCarbon Joint Conference; May 15, 2005 - May 19, 2005; Argonne, IL
Country of Publication:
United States
Language:
ENGLISH
Subject:
36 MATERIALS SCIENCE; 77 NANOSCIENCE AND NANOTECHNOLOGY; CARBON; DIAMONDS; FULLERENES; PHASE DIAGRAMS; PHASE STABILITY; PHASE TRANSFORMATIONS; NANOSTRUCTURES; MATHEMATICAL MODELS; MOLECULAR STRUCTURE

Citation Formats

Barnard, A. S. Theory and modelling of nanocarbon phase stability.. United States: N. p., 2006. Web. doi:10.1016/j.diamond.2005.05.007.
Barnard, A. S. Theory and modelling of nanocarbon phase stability.. United States. doi:10.1016/j.diamond.2005.05.007.
Barnard, A. S. Sun . "Theory and modelling of nanocarbon phase stability.". United States. doi:10.1016/j.diamond.2005.05.007.
@article{osti_979539,
title = {Theory and modelling of nanocarbon phase stability.},
author = {Barnard, A. S.},
abstractNote = {The transformation of nanodiamonds into carbon-onions (and vice versa) has been observed experimentally and has been modeled computationally at various levels of sophistication. Also, several analytical theories have been derived to describe the size, temperature and pressure dependence of this phase transition. However, in most cases a pure carbon-onion or nanodiamond is not the final product. More often than not an intermediary is formed, known as a bucky-diamond, with a diamond-like core encased in an onion-like shell. This has prompted a number of studies investigating the relative stability of nanodiamonds, bucky-diamonds, carbon-onions and fullerenes, in various size regimes. Presented here is a review outlining results of numerous theoretical studies examining the phase diagrams and phase stability of carbon nanoparticles, to clarify the complicated relationship between fullerenic and diamond structures at the nanoscale.},
doi = {10.1016/j.diamond.2005.05.007},
journal = {Diamond Related Mater.},
number = 2-3 ; 2006,
volume = 15,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}

Conference:
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  • We review, briefly, the first principles KKR--CPA theory of the electronic structure and energetics of alloys in which compositional disorder plays a role. We also review the first principles theories of ordering and alloy phase stability that are built on the KKR--CPA description of the disordered state. We point out a number of underlying electronic driving mechanisms of ordering and clustering that have been uncovered. Specifically, we emphasizxe the important role that Fermi surface nesting plays in driving specific instabilites. Using a newly developed method for treating the effects of disorder in alloys that have complex lattices we present resultsmore » for the ordering energies of beta phase Ni{sub c}Al({sub 1-c}) alloys. Finally, we show alloy Fermi surfaces'' in {beta}-phase Ni{sub 0.625}Al{sub 0.375} that support the notion that the pre-martensitic phenomena observed in this alloy are Fermi surface driven.« less
  • We review, briefly, the first principles KKR--CPA theory of the electronic structure and energetics of alloys in which compositional disorder plays a role. We also review the first principles theories of ordering and alloy phase stability that are built on the KKR--CPA description of the disordered state. We point out a number of underlying electronic driving mechanisms of ordering and clustering that have been uncovered. Specifically, we emphasizxe the important role that Fermi surface nesting plays in driving specific instabilites. Using a newly developed method for treating the effects of disorder in alloys that have complex lattices we present resultsmore » for the ordering energies of beta phase Ni{sub c}Al({sub 1-c}) alloys. Finally, we show alloy ``Fermi surfaces`` in {beta}-phase Ni{sub 0.625}Al{sub 0.375} that support the notion that the pre-martensitic phenomena observed in this alloy are Fermi surface driven.« less
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