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Title: Mesoscale modeling of irreversible volume growth in powders of anisotropic crystals

Abstract

Careful thermometric analysis (TMA) on powders of micron-sized triamino-trinitrobenzene (TATB) crystallites are shown to display irreversible growth in volume when subjected to repeated cycles of heating and cooling. Such behavior is counter-intuitive to typical materials response to simulated annealing cycles in atomic-scale molecular dynamics. However, through coarse-grained simulations using a mesoscale Hamiltonian we quantitatively reproduce irreversible growth behavior in such powdered material. We demonstrate that irreversible growth happens only in the presence of intrinsic crystalline anisotropy, and is mediated by particles much smaller than the average crystallite size.

Authors:
; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
940149
Report Number(s):
UCRL-JRNL-221255
Journal ID: ISSN 0003-6951; APPLAB; TRN: US200823%%527
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters, vol. 90, N/A, June 21, 2007, pp. 254105; Journal Volume: 90
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ANISOTROPY; ANNEALING; HAMILTONIANS; HEATING; SIMULATION; TATB

Citation Formats

Gee, R, Maiti, A, and Fried, L. Mesoscale modeling of irreversible volume growth in powders of anisotropic crystals. United States: N. p., 2006. Web.
Gee, R, Maiti, A, & Fried, L. Mesoscale modeling of irreversible volume growth in powders of anisotropic crystals. United States.
Gee, R, Maiti, A, and Fried, L. Fri . "Mesoscale modeling of irreversible volume growth in powders of anisotropic crystals". United States. doi:. https://www.osti.gov/servlets/purl/940149.
@article{osti_940149,
title = {Mesoscale modeling of irreversible volume growth in powders of anisotropic crystals},
author = {Gee, R and Maiti, A and Fried, L},
abstractNote = {Careful thermometric analysis (TMA) on powders of micron-sized triamino-trinitrobenzene (TATB) crystallites are shown to display irreversible growth in volume when subjected to repeated cycles of heating and cooling. Such behavior is counter-intuitive to typical materials response to simulated annealing cycles in atomic-scale molecular dynamics. However, through coarse-grained simulations using a mesoscale Hamiltonian we quantitatively reproduce irreversible growth behavior in such powdered material. We demonstrate that irreversible growth happens only in the presence of intrinsic crystalline anisotropy, and is mediated by particles much smaller than the average crystallite size.},
doi = {},
journal = {Applied Physics Letters, vol. 90, N/A, June 21, 2007, pp. 254105},
number = ,
volume = 90,
place = {United States},
year = {Fri May 05 00:00:00 EDT 2006},
month = {Fri May 05 00:00:00 EDT 2006}
}
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