1,1'-Azobis(1,2,3,4-tetrazole) is a highly explosive and unstable chemical compound discovered by Thomas M. Klapötke and Davin G. Piercey at LMU Munich which contains a long continuous chain of nitrogen atoms, with an unbroken chain of ten nitrogen atoms contained within two 1,2,3,4-tetrazole rings and an azo bridge. It is related to 1,1'-azobis-1,2,3-triazole which has a similar structure but with an 8 nitrogen atom chain through the replacement of two N atoms with C-H groups. It is stable only up to 80 °C and is reported to be one of the most sensitive explosives in existence.we experienced several inadvertent explosions during handling such as allowing the dry powder to slide down the inside of a Raman tube or slowing down the rotation rate of a rotary evaporator as 4 crystallized. The material demands the utmost care in handling, and the sensitivities were well below the measurable limit of our safety characterization equipment; the material violently explodes when impacted with a 150 g hammer at 2 cm. It is among the most sensitive materials that we have handled