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Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Molecular conformational stability in cyclotrimethylene trinitramine crystals
1Department of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, USA.
The Journal of Chemical Physics
|July 20, 2011
Summary
The study reveals how cyclotrimethylene trinitramine (RDX) molecule conformations shift within crystals. Strain and temperature influence these RDX conformation changes, impacting material properties.
Area of Science:
- Computational chemistry
- Materials science
- Solid-state physics
Background:
- Cyclotrimethylene trinitramine (RDX) exists in multiple conformations.
- The Caae conformation is stable in α-RDX crystals at room temperature and atmospheric pressure.
- Other conformations, like Caee, can stabilize under specific conditions such as crystal strain.
Purpose of the Study:
- To evaluate the transition barriers between RDX conformers.
- To investigate the influence of vacuum and crystal environments on RDX conformer stability.
- To understand the factors affecting the concentration and behavior of RDX conformers in α-RDX crystals.
Main Methods:
- Molecular modeling was employed to calculate transition barriers.
- Analysis of elastic and electrostatic interactions between conformers.
- Investigation of stochastic processes and temporal correlations in conformer transitions.
Main Results:
- The Caae conformation is the most stable in unstrained α-RDX crystals.
- The Caee conformation stabilizes in strained α-RDX crystals, with concentration dependent on strain and temperature.
- Conformer interactions lead to spatial clustering and field-mediated spatial interactions.
- Conformer transitions exhibit stochastic behavior with temporal correlations.
- Intra-molecular effective temperature fluctuations correlate with conformation transitions.
Conclusions:
- RDX conformer stability and transitions are significantly influenced by crystal strain and temperature.
- Interactions between RDX conformers play a crucial role in their spatial organization and dynamic behavior.
- The study quantifies the relationship between intra-molecular temperature fluctuations and RDX conformation changes.
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