Coordination chemistry with 1-methyl-5H-tetrazole: cocrystallization, laser-ignition, lead-free primary explosives – one ligand, three goals

Abstract

Numerous energetic coordination complexes (MnII, FeII, CoII, NiII, CuII, ZnII, and AgI) using 1-methyl-tetrazole as the ligand were synthesized and tuned by different counteranions (e.g. NO3−, ClO4−, picrate, and styphnate). They show great potential for mechanical or optical initiation systems.

Methylsemicarbazide as a Ligand in Late 3d Transition Metal Complexes

“…Numerous decomposition paths and mechanisms are possible. Similar phenomena have already been described in the literature . The ligand vaporization tendency and the relating bond strengths are strongly influenced by the metal [Zn(ClO 4 ) 2 ( 12 ) vs. Ni(ClO 4 ) 2 ( 18 ), Figure S12 in the Supporting Information], anion [Cu(NO 3 ) 2 ( 6 ) vs. Cu(ClO4) 2 ( 19 ), Figure S12] and the corresponding coordination environment (Zn(ClO 4 ) 2 , ( 11 ) vs. ( 12 )).…”

“…Looking at the absorption intensity of the coordination compounds at the irradiated wavelength of 915 nm (Figure ), one could possibly derive a direct connection to the performed laser ignition because all complexes could be initiated. However, the laser initiation capability depends not only on the absorption but also on multiple other factors like crystal structure or the coordination environment . It can be concluded that deflagration or detonation of the complexes after exposure to laser irradiation occurs possibly if the compounds possess high mechanical sensitivities.…”

“…Similar phenomenah ave already been described in the literature. [27][28][29] The ligand vaporization tendency and the relatingb onds trengths are strongly influenced by the metal [Zn(ClO 4 ) 2 (12)v s. Ni(ClO 4 ) 2 (18), Figure S12i The water-free metal(II) MSC picrate coordination compounds showedr elatively high thermals tabilities ranging from 179 8Cf or 19 up to 217 8Cf or 23 (Figure 14). Their exothermic decomposition temperaturesi ncrease in the following order:…”

“…However,t he laser initiation capability dependsn ot only on the absorption but also on multiple other factors like crystal structureo rt he coordination environment. [29] It can be concluded that deflagration or detonation of the complexesa fter exposure to laser irradiation occursp ossibly if the compounds possessh igh mechanical sensitivities. Considering the influence of the metal, anion and ligand on the laser initiation process, as well as that the mechanism itself has not been clarified yet, future investigations will be needed to fully understand the laser initiation of energetic materials.…”

1‐AminoTriazole Transition‐Metal Complexes as Laser‐Ignitable and Lead‐Free Primary Explosives

“…=194 °C). Analogous complexes with 1‐methyl‐5 H ‐tetrazole or 1‐amino‐5 H ‐tetrazole interestingly show almost the same trend, which could be a useful indicator for the design of future energetic complexes with high‐temperature stability . Compared with the copper(II) perchlorate complex of 4‐ATRI with a decomposition temperature of 250 °C, it becomes clear that the formation of closed octahedral coordination spheres with the absence of polymeric structures leads to a significant decrease in thermal stability.…”