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Shocked Energetic Molecular Materials: Chemical Reaction Initiation and Hot Spot Formation

Published online by Cambridge University Press:  15 February 2011

M. D. Fayer
Affiliation:
Department of Chemistry, Stanford University, Stanford, CA 94305
Andrei Tokmakoff
Affiliation:
Department of Chemistry, Stanford University, Stanford, CA 94305
Dana D. Dlott
Affiliation:
School of Chemical Sciences, University of Illinois at Urbana-Champaign, Urbana, IL 61801
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Abstract

A theoretical model is developed to describe multiphonon up-pumping of internal vibrations. The dominant mechanism for up-pumping is anharmonic coupling of excited phonon modes with low frequency molecular vibrations, termed doorway modes. Quantitative calculations were performed which show the extent and rate of multiphonon up-pumping caused by shock excitation. The time dependence of chemical reactivity behind the front is calculated using reaction rate laws for the decomposition of nitramine explosives. A mechanism for hot spot formation, based on defect induced local increases in anharmonic coupling, is discussed.

Type
Research Article
Copyright
Copyright © Materials Research Society 1993

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