May 2, 2024

New Explosive Compound Synthesized From Strange World of High-Pressure Chemistry

Microphotographs of laser-heated potassium azide samples at pressures of 500,000 atmospheres (left) and 300,000 environments (right). Its a crystal produced at a pressure of 450,000 atmospheres. When formed, it can continue at about half that pressure,” states Alexander Goncharov, a staff scientist at Carnegie Institution of Washington, where the experiment was run. “In that crystal, the nitrogen atoms assemble into hexagons, where the bond in between each two adjacent nitrogens is intermediate between a single and a double bond.

While such unique nitrogen crystals definitely could blow up, going back to the familiar triple-bonded N2 gas, their synthesis requires pressures that are too expensive for any practical applications. This leads researchers to explore other nitrogen-rich compounds, such as the one obtained for the first time in the study published today, led by Carnegies Alexander F. Goncharov.
As soon as formed, it can continue at about half that pressure,” states Alexander Goncharov, a personnel researcher at Carnegie Institution of Washington, where the experiment was run. “In that crystal, the nitrogen atoms put together into hexagons, where the bond between each 2 nearby nitrogens is intermediate in between a single and a double bond.
The researchers admit that the new product falls short of useful applications, because the synthesis pressure required is still expensive– 100,000 environments would be more realistic– but it certainly constitutes a step in the best direction and offers exciting fundamental chemistry insights.
” This new high energy density product is another example of the strange chemistry of high pressures,” Oganov says, including that his recently published research study (find out more), which revamped the fundamental concept of electronegativity making it appropriate under pressure, is a beneficial structure for understanding the unusual nitrogen-rich products, in addition to other exotic compounds spanning the entire routine table of aspects.
Referral: “Stabilization of hexazine rings in potassium polynitride at high pressure” 21 April 2022, Nature Chemistry.DOI: 10.1038/ s41557-022-00925-0.

Explosion animation artists concept.
Researchers from Skoltech, Carnegie Institution of Washington, Howard University, the University of Chicago, and the Chinese Academy of Sciences Institute of Solid State Physics have manufactured K2N6, an unique compound containing N6 groups and packing explosive amounts of energy. While the team had to create synthesis pressures several times greater than it would require to make the material helpful outside the lab as an explosive or rocket propellant, the experiment to be released today (April 21, 2022) in Nature Chemistry takes us one action closer to what would be technically applicable.
Nitrogen is at the heart of most chemical explosives, from TNT to gunpowder. The reason for this is that a nitrogen atom has three unpaired electrons itching to form chemical bonds, and integrating 2 such atoms in an N2 particle in which the atoms share 3 electron sets is without a doubt the most energy-efficient way of scratching that itch. This implies that substances with a lot of nitrogen atoms taken part in other, less energetically beneficial bonds are always on the edge of an explosive reaction that produces N2 gas.
Microphotographs of laser-heated potassium azide samples at pressures of 500,000 atmospheres (left) and 300,000 atmospheres (right). The white to light-blue locations on the exterior are K1N3. Towards the center, the material has actually transformed into K2N6 in the left picture and a strange and poorly comprehended compound with the formula K3( N2) 4 on the. Credit: Yu Wang et al./ Nature Chemistry
Teacher Artem R. Oganov of Skoltech, who was accountable for the computations in the research study reported in this story, comments: “An idea has existed for a very long time that pure nitrogen might be the ultimate chemical explosive if manufactured in a kind including no N2 particles. And undoubtedly, previous research study has actually shown that at pressures of over 1 million environments, nitrogen does form structures where any two surrounding atoms only share one electron set, not three.”