Energetic materials under high pressures and temperatures: stability, polymorphism and decomposition of RDX

Dreger, Zbigniew A.

doi:10.1088/1742-6596/377/1/012047

Cited by 5 publications

(4 citation statements)

References 13 publications

(28 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Secondary energetics, such as FOX-7, nitrotriazolone, or TATB, require higher input energies and are often detonated by the shock wave of a primary energetic material . Tuning sensitivity properties is now a pressing area of research, with large screenings of novel molecules, crystal phases (polymorphs), − and multicomponent materials (cocrystals and salts) − being conducted. At present, the development of novel energetic materials requires production and experimental testing, with a posteriori rationalization of their properties.…”

Section: Introductionmentioning

confidence: 99%

A Pathway to the Athermal Impact Initiation of Energetic Azides

et al. 2018

View full text Add to dashboard Cite

Energetic materials (explosives, propellants, and pyrotechnics) are used in a broad range of public and private sector applications. The design of novel, safe materials is therefore of critical importance. At present, physical mechanisms able to rationalize the impact sensitivity properties of energetic materials remain limited. Investigation therefore has required lengthy synthesis and experimental testing. On the basis of knowledge of the effects of mechanical impact, an ab initio model is developed to rationalize and describe the impact sensitivity of a series of crystalline energetic azide materials. It is found that electronic excitation of the azido anion is sufficient to permit bond rupture and therefore offers a plausible mechanism for initiation of these materials. The athermal excitation can be achieved through consideration of nonadiabatic vibronic processes. Across the series of azides studied here, the electronic structure of the azido anion is found to remain largely constant. By considering only the relative rates of vibrational energy transfer within the crystalline materials, it is found that a direct correlation exists between the relative impact sensitivity and the rate of energy up-conversion. Thus, the present contribution demonstrates a fully ab initio method to describe the athermal initiation of ideal, crystalline energetic materials and predict their relative sensitivity. Without the need for any experimental input beyond a crystal structure, this method therefore offers a means to selectively design novel materials for targeted application.

show abstract

Section: Introductionmentioning

confidence: 99%

A Pathway to the Athermal Impact Initiation of Energetic Azides

et al. 2018

View full text Add to dashboard Cite

show abstract

“…The non-conserved order parameter is associated with the molecular confirmation and crystal structure. The secondary phase transformation has not been observed experimentally in the single crystal of RDX shocked below decomposition threshold (Patterson et al, 2007;Dreger, 2012). Hence, we do not consider secondary phase transformation in this model.…”

Section: Phase-field Modelmentioning

confidence: 98%

A phase-field model for shock-induced α-γ phase transition of RDX

Rahul

2017

International Journal of Plasticity

View full text Add to dashboard Cite

A thermodynamically consistent continuum phase-field model has been developed to investigate the role of shock-induced solid-solid phase transformation in the deformation mechanisms of molecular single crystals. The effects of microstructural evolution and phase transformation are distinguished and modeled within a crystal plasticity framework that is developed for single crystals at high strain rate. When applied to 1,3,5trinitroperhydro-1,3,5-triazine (RDX) single crystal, the model predicts α-γ phase transition within the experimentally observed range of shock stresses. Phase-field simulations suggest that the α-γ phase transition requires finite time to occur, where plasticity tends to delay the transition. Phase transformation is associated with stress relaxation, and increased temperature rise and associated shock-sensitivity. The shock response of α-γ phase transition is orientation dependent.

show abstract

“…RDX is known to exist in five crystalline polymorphs (α, β, γ, ε, and δ), whereas HMX has four crystalline phases (α, β, γ, and δ), depending on different temperature and pressure conditions. Phase transitions at high pressure are identified by using vibrational spectroscopy. − …”

Section: Introductionmentioning

confidence: 99%

“…

Anion photoelectron spectroscopy, supported by density functional theory (DFT) calculations, is employed to study energetic materials RDX (3,5-trinitroperhydro-1,3,5triazine) and 3,5,3,5,. Their isolated anions and decomposition products are generated by matrix-assisted laser desorption ionization (MALDI).

…”

mentioning

confidence: 99%

RDX- and HMX-Related Anionic Species Explored by Photoelectron Spectroscopy and Density Functional Theory

Zeng

Bernstein

2018

J. Phys. Chem. C

View full text Add to dashboard Cite

Anion photoelectron spectroscopy, supported by density functional theory (DFT) calculations, is employed to study energetic materials RDX (3,5-trinitroperhydro-1,3,5-triazine) and HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine). Their isolated anions and decomposition products are generated by matrix-assisted laser desorption ionization (MALDI). Their anionic parent species are not observed, but instead accessible fragmentation ions are detected. The vertical detachment energies (VDEs) of these anionic, dissociation-generated species are experimentally determined, and the corresponding structures are identified by comparing DFT-calculated VDEs to the experimental ones. RDX– and HMX– can fragmentate through the loss of HNO2, NO2, and NCH2 groups. RDX– loses up to two NO2 groups and one NCH2 moiety, and HMX– can fragment by up to three NO2 groups and two NCH2 moieties. The mass units of (RDX – H – NO2)−, (RDX – H – (NO2)2)−, and (RDX – NCH2 – (NO2)2)− are the same as those of (HMX – H – (NO2)2 – NCH2)−, (HMX – H – (NO2)3 – NCH2)−, and (HMX – (NO2)3 – (NCH2)2)−, respectively. These dissociation-related anions with the same mass units share nearly identical photoelectron spectra and geometrical structures, which suggest structural and dissociation routine similarities between RDX and HMX anions. By way of comparison, energetic material TATB (2,4,6-triamino-1,3,5-trinitrobenzene) has also been considered: Its parent anion generated through MALDI processes can be observed in the mass spectrum. The observation of TATB– parent anion, but not RDX– and HMX– parent anions, is consistent with TATB’s higher thermal stability than those of RDX and HMX.

show abstract

Energetic materials under high pressures and temperatures: stability, polymorphism and decomposition of RDX

Cited by 5 publications

References 13 publications

A Pathway to the Athermal Impact Initiation of Energetic Azides

A Pathway to the Athermal Impact Initiation of Energetic Azides

A phase-field model for shock-induced α-γ phase transition of RDX

RDX- and HMX-Related Anionic Species Explored by Photoelectron Spectroscopy and Density Functional Theory

Contact Info

Product

Resources

About