Carbon nitrides are compounds consisting only of carbon and nitrogen atoms. Carbon nitrides are also known as organic semiconductors with a band gap of 2.7 eV. Due to its hydrogen-bonding motifs and electron-rich properties, this carbon material is considered a potential candidate for material applications in carbon supplementation.^[1]

Covalent network compounds

Beta carbon nitride - a solid with a formula β-C₃N₄, which is predicted to be harder than diamond.
Graphitic carbon nitride - g-C₃N₄, with important catalytic and sensor properties.^[2]
C₃N₅ - a combined triazole and triazine framework.^[3]
MCN-12 (C₃N₆) and MCN-13 (C₃N₇).^[4]

Azafullerenes

Azafullerenes are a class of heterofullerenes in which the element substituting for carbon is nitrogen.^[5] Examples include (C₅₉N)₂ (biazafullerenyl),^[6] C₅₈N₂ (diaza[60]fullerene), C₅₇N₃ (triaza[60]fullerene) and C₄₈N₁₂.

Cyanofullerenes

Cyanofullerenes are a class of modified fullerenes in which cyano- groups are attached to a fullerene skeleton. These have the formula C₆₀(CN)_2n, where n takes the values 1 to 9.

Cyanogen

Cyanogen - C₂N₂ (N≡C−C≡N)
Isocyanogen - C₂N₂ (⁻C≡N⁺−C≡N)
Diisocyanogen - C₂N₂ (⁻C≡N⁺−⁺N≡C⁻)
Paracyanogen - a cyanogen polymer, (NCCN)_n
Paraisocyanogen - a cyanogen polymer, (CNCN)_n

Percyanoalkynes, -alkenes and -alkanes

dicyanoacetylene - C₄N₂ or N≡C−C≡C−C≡N, also called carbon subnitride or but-2-ynedinitrile
tetracyanoethylene - C₆N₄ or (N≡C−)₂C=C(−C≡N)₂
tetracyanomethane - C₅N₄ or C(−C≡N)₄
2,2-diisocyanopropanedinitrile - C₅N₄ or (⁻C≡N⁺−)₂C(−C≡N)₂
hexacyanoethane - C₈N₆ or (N≡C−)₃C−C(−C≡N)₃
hexacyanocyclopropane - C₉N₆ or C₃(CN)₆
hexacyanobutadiene^[7] - C₁₀N₆ or C₄(CN)₆

Dicyanopolyynes

Dicyanopolyynes are composed of a chain of carbon atoms with alternating single and triple bonds, terminated by nitrogen atoms. Although not a polyyne dicyanoacetylene (N≡C−C≡C−C≡N) otherwise fits within this series.

C₆N₂ or N≡C−C≡C−C≡C−C≡N, dicyanobutadiyne (dicyanodiacetylene)
C₈N₂ or N≡C−C≡C−C≡C−C≡C−C≡N, dicyanohexatriyne
C₁₀N₂ or N≡C−C≡C−C≡C−C≡C−C≡C−C≡N
C₁₂N₂ or N≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡N
C₁₄N₂ or N≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡N
C₁₆N₂ or N≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡N
C₁₈N₂ or N≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡N
C₂₀N₂ or N≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡N
C₂₂N₂ or N≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡C−C≡N

Perazidoalkynes, -alkenes and -alkanes

tetraazidomethane - CN₁₂ or C(−N=N⁺=N⁻)₄

Percyanoheterocycles

pentacyanopyridine - C₁₀N₆
tetracyanopyrazine - C₈N₆
tricyanotriazine - C₆N₆^[8]
tetracyano-bitriazine - C₁₀N₁₀^[8]
dicyanotetrazine - C₄N₆
hexacyanotrisimidazole - C₁₅N₁₂
hexacyanohexaazatriphenylene - C₁₈N₁₂

Aromatic cyanocarbons

hexacyanobenzene - C₁₂N₆
octacyanonaphthalene - C₁₈N₈
decacyanoanthracene - C₂₄N₁₀

Other compounds

cyanonitrene - CN₂ or [N≡C−N ⇌ ⁻N=C=N⁺ ⇌ +N=C=N⁻ ⇌ N−C≡N] (one of the nitrogens is univalent)
azodicarbonitrile - C₂N₄ or N≡C−N=N−C≡N, cis and trans isomers
cyanogen azide - CN₄ or N≡C−N=N⁺=N⁻
1-diazidocarbamoyl-5-azidotetrazole - C₂N₁₄
2,2′-azobis(5-azidotetrazole) - C₂N₁₆
triazidotriazine (cyanuric triazide) - C₃N₁₂ (C₃N₃(N₃)₃)
triazidoheptazine - C₆N₁₆ (C₆N₇(N₃)₃)
tricyanomethanimine (dicyanomethylene-cyanamide) - C₄N₄ or N≡C−N=C(−C≡N)₂
diazidodicyanoethylene - C₄N₈ or (⁻N=N⁺=N−)₂C=C(−C≡N)₂ and (⁻N=N⁺=N−)(N≡C−)C=C(−N=N⁺=N⁻)(−C≡N), cis and trans
dicyanodiazomethane - C₃N₄ or (N≡C−)₂C=N⁺=N⁻
dicyanocarbene - C₃N₂ or C^II(−C≡N)₂ (and isomers cyanoisocyanocarbene ⁻C≡N⁺−C^II−C≡N, diisocyanocarbene ⁻C≡N⁺−C^II−⁺N≡C⁻, 3-cyano-2H-azirenylidene and 3-isocyano-2H-azirenylidene)
1,3,5-triazido-2,4,6-tricyanobenzene - C₉N₁₂ (C₆(CN)₃(N₃)₃)
nitrogen tricyanide N(−C≡N)₃ and carbon bis(cyanamide) N≡C−N=C=N−C≡N, two formal monomers of polymeric C₃N₄

Anions and functional groups

cyanide - ⁻C≡N ion, cyanide −C≡N and isocyanide −⁺N≡C⁻ functional groups
dicyanamide - N(CN)−2 or ⁻N(−C≡N)₂
tricyanomethanide - C(CN)−3 or ⁻C(−C≡N)₃
pentacyanoethanide - C₂(CN)−5 or (N≡C−)₂C⁻−C(−C≡N)₃
pentacyanopropenide (pentacyanoallyl anion) - C₃(CN)−5
2-dicyanomethylene-1,1,3,3-tetracyanopropanediide C₁₀N2−6
tricyanomelaminate anion - C₃N₃(NCN)3−3
melonate - C₆N₇(NCN)3−3
cyanofullerene anions - C₆₀(CN)_n⁻ (n odd) and C₆₀(CN)_n²⁻ (n even)
cyanoacetlyide - C₃N⁻ or ⁻C≡C−C≡N
cyanobutadiynylide - C₅N⁻ or ⁻C≡C−C≡C−C≡N
cyanopolyynide anions - C_nN⁻ (n odd)

References

^ Vinodh, Rajangam; Atchudan, Raji; Yi, Moonsuk; Kim, Hee-Je (2022). "Synthesis and properties of carbon nitride materials". Nanostructured Carbon Nitrides for Sustainable Energy and Environmental Applications. pp. 1–18. doi:10.1016/B978-0-12-823961-2.00008-2. ISBN 978-0-12-823961-2.
^ Lv, Hongying; Teng, Zhenyuan; Wang, Sicong; Feng, Ke; Wang, Xiaoli; Wang, Chengyin; Wang, Guoxiu (March 2018). "Voltammetric simultaneous ion flux measurements platform for Cu2+, Pb2+ and Hg2+ near rice root surface: Utilizing carbon nitride heterojunction film modified carbon fiber microelectrode". Sensors and Actuators B: Chemical. 256: 98–106. doi:10.1016/j.snb.2017.10.053.
^ I. Y. Kim, S. Kim, X. Jin, S. Premkumar, G. Chandra, N.-S. Lee, G. P. Mane, S.-J. Hwang, S. Umapathy, A. Vinu, Angew. Chem. Int. Ed. 2018, 57, 17135. doi:10.1002/anie.201811061
^ Kim, I. Y., Kim, S., Premkumar, S., Yang, J.-H., Umapathy, S., Vinu, A., "Thermodynamically Stable Mesoporous C₃N₇ and C₃N₆ with Ordered Structure and Their Excellent Performance for Oxygen Reduction Reaction". Small 2020, 16, 1903572. doi:10.1002/smll.201903572
^ D.J. Harris, Discovery of Nitroballs: Research in Fullerene Chemistry, 1993 California State Science Fair, http://www.usc.edu/CSSF/History/1993/S05.html Archived 2016-03-04 at the Wayback Machine
^ Hummelen et al, "Isolation of the Heterofullerene C59N as Its Dimer (C59N)2", Science 269: 1554-1556 (1995). doi:10.1126/science.269.5230.1554
^ O.W.Webster, Hexacyanobutadiene, J. Am. Chem. Soc. 86(14): 2898–2902 (1964)
^ ^a ^b Sesto et al, "Chemical Reduction of 2,4,6-Tricyano-1,3,5-triazine and 1,3,5-Tricyanobenzene. Formation of Novel 4,4',6,6'-Tetracyano-2,2'-bitriazine and Its Radical Anion", J. Org. Chem. 68: 3367-3379 (2003). doi:10.1021/JO025833H

v t e Inorganic compounds of carbon and related ions
Compounds	CF CO CO₂ CO₃ CO₄ CO₅ CO₆ COS CS C₂S₂ CS₂ CSe₂ C₃O₂ C₃S₂ SiC
Carbon ions	Carbides [:C≡C:]²⁻, [::C::]⁴⁻, [:C=C=C:]⁴⁻ Cyanide [:C≡N:]⁻ Cyanate [:O−C≡N:]⁻ Thiocyanate [:S−C≡N:]⁻ Fulminate [:C≡N−O:]⁻ Thiofulminate [:C≡N−S:]⁻
Nanostructures	Graphite intercalation compounds Fullerides
Oxides and related	Oxides Nitrides Metal carbonyls Carbonic acid Bicarbonates Carbonates