hexazine

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| verifiedrevid = 414056174

| ImageFile = Hexazine.svg

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| ImageSize = 244

| ImageName = Kekulé and aromatic, skeletal formulae of hexazine

| ImageFile2 = Hexazine3.png

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| ImageSize2 = 244

| ImageName2 = Ball and stick, and spacefill models of hexazine

| PIN = Hexazine (preselected name)

| SystematicName = Hexaazabenzene

| OtherNames = Hexazabenzene{{Cite web|url = https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=11966278&loc=ec_rcs|title = Hexazine - PubChem Public Chemical Database|work = The PubChem Project|location = USA|publisher = National Center for Biotechnology Information}}
Hexaazabenzene
Azabenzene

|Section1={{Chembox Identifiers

| CASNo_Ref = {{cascite|changed|??}}

| CASNo = 7616-35-5

| PubChem = 11966278 {{PubChem|correct|pubchem}}

| ChemSpiderID = 10140271

| ChemSpiderID_Ref = {{chemspidercite|changed|chemspider}}

| ChEBI_Ref = {{ebicite|changed|EBI}}

| ChEBI = 36869

| Gmelin = 1819

| SMILES = n1nnnnn1

| SMILES1 = N1=NN=NN=N1

| StdInChI = 1S/N6/c1-2-4-6-5-3-1

| StdInChI_Ref = {{stdinchicite|changed|chemspider}}

| StdInChIKey = YRBKSJIXFZPPGF-UHFFFAOYSA-N

| StdInChIKey_Ref = {{stdinchicite|changed|chemspider}}

}}

|Section2={{Chembox Properties

| N=6

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Hexazine (also known as hexaazabenzene) is a hypothetical allotrope of nitrogen composed of 6 nitrogen atoms arranged in a ring-like structure analogous to that of benzene. As a neutrally charged species, it would be the final member of the azabenzene (azine) series, in which all of the methine groups of the benzene molecule have been replaced with nitrogen atoms. The two last members of this series, hexazine and pentazine, have not been observed, although all other members of the azine series have (such as pyridine, pyrimidine, pyridazine, pyrazine, triazines, and tetrazines).

While a neutrally charged hexazine species has not yet been synthesized, two negatively charged variants, [N₆]^2-{{Cite journal |last1=Wang |first1=Yu |last2=Bykov |first2=Maxim |last3=Chepkasov |first3=Ilya |last4=Samtsevich |first4=Artem |last5=Bykova |first5=Elena |last6=Zhang |first6=Xiao |last7=Jiang |first7=Shu-qing |last8=Greenberg |first8=Eran |last9=Chariton |first9=Stella |last10=Prakapenka |first10=Vitali B. |last11=Oganov |first11=Artem R. |last12=Goncharov |first12=Alexander F. |date=July 2022 |title=Stabilization of hexazine rings in potassium polynitride at high pressure |url=https://www.nature.com/articles/s41557-022-00925-0 |journal=Nature Chemistry |language=en |volume=14 |issue=7 |pages=794–800 |doi=10.1038/s41557-022-00925-0 |pmid=35449217 |issn=1755-4330|arxiv=2010.15995 |bibcode=2022NatCh..14..794W |s2cid=226222305 }} and [N₆]^4-,{{Cite journal |last1=Laniel |first1=Dominique |last2=Trybel |first2=Florian |last3=Yin |first3=Yuqing |last4=Fedotenko |first4=Timofey |last5=Khandarkhaeva |first5=Saiana |last6=Aslandukov |first6=Andrey |last7=Aprilis |first7=Georgios |last8=Abrikosov |first8=Alexei I. |last9=Bin Masood |first9=Talha |last10=Giacobbe |first10=Carlotta |last11=Bright |first11=Eleanor Lawrence |last12=Glazyrin |first12=Konstantin |last13=Hanfland |first13=Michael |last14=Wright |first14=Jonathan |last15=Hotz |first15=Ingrid |date=2023-03-06 |title=Aromatic hexazine [N6]4− anion featured in the complex structure of the high-pressure potassium nitrogen compound K9N56 |url=https://www.nature.com/articles/s41557-023-01148-7 |journal=Nature Chemistry |volume=15 |issue=5 |language=en |pages=641–646 |doi=10.1038/s41557-023-01148-7 |pmid=36879075 |bibcode=2023NatCh..15..641L |s2cid=257377020 |issn=1755-4349}} have been produced in potassium-nitrogen compounds under very high pressures (> 40 GPa) and temperatures (> 2000 K). In particular, [N₆]^4- is aromatic, respecting Hückel's rule, while [N₆]^2- is anti-aromatic.