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Intercomparison of calorimetry, Raman spectroscopy, and second harmonic generation applied to solid-solid phase
L Smilowitz1, B F Henson, J J Romero
1Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA. smilo@lanl.gov
The Journal of Physical Chemistry. A
|August 12, 2009
Summary
This study evaluates techniques for measuring solid-solid phase transition kinetics. The beta to delta phase transition of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine was used for direct comparison.
Area of Science:
- Materials Science
- Chemical Kinetics
- Crystallography
Background:
- Solid-solid phase transitions are crucial in materials science.
- Accurate kinetic measurements are essential for understanding and controlling these transitions.
- Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) is an energetic material exhibiting polymorphic phase transitions.
Purpose of the Study:
- To compare various observables for measuring the kinetics of solid-solid phase transitions.
- To assess the relative advantages and disadvantages of different measurement techniques.
- To provide a direct comparison of results for a specific energetic material transition.
Main Methods:
- Comparative analysis of different kinetic measurement observables.
- Experimental investigation of the beta to delta polymorphic phase transition.
- Application of techniques to octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine.
Main Results:
- Identification of the most suitable observables for kinetic studies.
- Detailed comparison of technique performance for the HMX transition.
- Quantification of kinetic parameters for the beta to delta phase transition.
Conclusions:
- Certain observables offer superior advantages for kinetic measurements of solid-solid phase transitions.
- The findings provide valuable insights for selecting appropriate methods in materials research.
- This work facilitates a deeper understanding of phase transition dynamics in energetic materials.
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