High Pressure Behavior of Crystalline Dihydroxylammonium 5,5'-Bistetrazole- 1,1'-Diolate: First-Principles Study

Abstract

publicado na web em 25/09/2017Density functional theory (DFT) periodic calculations were performed to study the geometrical and electronic structures of energetic compound dihydroxylammonium 5,5'-bistetrazole-1,1'-diolate (TKX-50) under the pressure ranging from 0 to 400 GPa. The optimized crystal structure by the local density approximation (LDA) with CA-PZ functional matches well with the experimental values under the ambient pressure. When the structural transformations occur under the pressure of 126, 288, and 334 GPa, with the pressure increasing, the lattice constants, unit cell volume, total energy, interatomic distances, bond angles, atomic charges, and bond populations of TKX-50 change gradually. First of all, TKX-50 is rearranged in the crystal and the improvement of the molecular planarity occurs. Next, structural transformation appears with the distortion of the tetrazole rings. Finally, the rotation of molecular conformation occurs. The results of the band gap and density of states show that TKX-50 crystal, with the increase of pressure, undergoes an electronic transition from the semiconductor to the metallic system. These results provide basic information for the high pressure behavior of crystalline TKX-50.

Theoretical study on intra-molecule interactions in TKX-50

“…11–32 Finally, there is significant interest in understanding the crystal structure and properties of TKX-50. 33–48…”

“…Finally, there is significant interest in understanding the crystal structure and properties of TKX-50. [33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48] Regarding the crystal structure and properties of TKX-50, most attention has been focused on the inter-and intramolecular interactions in the solid crystal. ZHU Zhou-Shuo et al employed the B3LYP method with the 6-31++G basis set to simulate the structure of TKX-50, revealing strong inter-and intra-molecular hydrogen bonds in the solid crystal.…”

An Overview on Synthesis, Explosion, Catalysis, Modification, and Application of Dihydroxylammonium 5,5′-Bistetrazole-1,1′-diolate (TKX-50)

“…Under high pressure, the molecular properties of TKX-50 change significantly. To explore the influence of high-pressure conditions on TKX-50, Yanc et al 54 conducted a study to investigate the effect of high pressure on the molecular properties of TKX-50. They utilized DFT calculations to analyze the geometric properties and electronic structure of TKX-50 at pressures ranging from 0 to 400 GPa.…”

Thermal Decomposition Characteristics and Thermal Safety of Dihydroxylammonium 5,5′-Bistetrazole-1,1′-diolate Based on Microcalorimetric Experiment and Decoupling Method

“…Due to the excellent comprehensive performance of TKX-50, it has attracted extensive attention from numerous researchers, despite extensive research on thermal decomposition mechanisms, − recrystallization, − synthesis, , high pressure stability. − Most of the experimental studies on thermal decomposition of TKX-50 were based on differential scanning calorimetry, thermogravimetry, and other instruments, as its dosage was too small (0.3–1.0 mg) to detect its heat signal effectively and accurately. Lack of experimental studies exist on the effects of relatively large mass effects on the thermal decomposition of TKX-50, and the thermal decomposition of TKX-50 had a complex reaction mechanism.…”