Polycyclic aromatic hydrocarbons

3-Methylcholanthrene

3-Methylcholanthrene (3MC, also abbreviated MCA) is a pentacyclic polycyclic aromatic hydrocarbon that acts as a potent carcinogen and aryl hydrocarbon receptor agonist in cancer research.

7,12-Dimethylbenz(a)anthracene

7,12-Dimethylbenz(a)anthracene (DMBA) is a potent carcinogenic polycyclic aromatic hydrocarbon, C20H16, requiring metabolic activation and used for about 60 years to induce hormone-dependent mammary tumors in laboratory rodents.

Acenaphthylene

Acenaphthylene, also known as cyclopenta[de]naphthalene, is a polycyclic aromatic hydrocarbon with formula C12H8, formed during incomplete combustion and occurring in crude oil, shale oil, and coal tar.

Benz[a]anthracene

Benz[a]anthracene, also written benzo[a]anthracene, is a four-ring polycyclic aromatic hydrocarbon (C18H12) found in cigarette smoke and classified as possibly carcinogenic to humans (IARC Group 2B).

Benzo(a)pyrene

Benzo(a)pyrene, also known as benzo-alpha-pyrene or BaP, is a five-ring polycyclic aromatic hydrocarbon formed by incomplete combustion of organic matter, and IARC classifies it as carcinogenic to humans.

Benzo[a]pyrene

Benzo[a]pyrene (BaP) is a five-ring polycyclic aromatic hydrocarbon with formula C20H12, formed during incomplete combustion of organic matter and classified by IARC as carcinogenic to humans.

Benzo[b]fluoranthene

Benzo[b]fluoranthene, also known as benz[e]acephenanthrylene, is a five-ring polycyclic aromatic hydrocarbon, C₂₀H₁₂, found in smoke, soot, coal tar, and creosote, and classified by the EPA as a probable human carcinogen.

Carbon nanobelt

A carbon nanobelt is a belt-shaped, fully fused carbon molecule, essentially a short segment of a carbon nanotube, first synthesized by Kenichiro Itami's group at Nagoya University in 2017.

Clar's goblet

Clar's goblet is a bowtie-shaped C38H18 polycyclic aromatic hydrocarbon proposed by Erich Clar in 1972 as the first concealed non-Kekulé nanographene, first synthesized in 2020.

Coronene

Coronene, also known as superbenzene, is a polycyclic aromatic hydrocarbon (C₂₄H₁₂) with seven peri-fused benzene rings, used as a laboratory model for graphene and interstellar PAHs.

Cycloparaphenylene

Cycloparaphenylene (CPP) is a hoop-shaped molecule of para-linked benzene rings, also called a carbon nanohoop, representing the shortest cross section of an armchair carbon nanotube and first synthesized in 2008.

Fluoranthene

Fluoranthene, also known as 1,2-benzacenaphthene, is a four-ring polycyclic aromatic hydrocarbon, C₁₆H₁₀, produced by pyrolysis of coal and petroleum and found in air, food, and cigarette smoke.

Fluorene

Fluorene, also called 9H-fluorene, is a tricyclic aromatic hydrocarbon (C13H10) obtained from coal tar and found in creosote and asphalt, used in OLEDs and peptide chemistry.

Indene

Indene (C₉H₈) is a bicyclic aromatic hydrocarbon, a benzene ring fused with cyclopentene, and the first pure PAH detected in interstellar space, in TMC-1 in 2021.

Infinitene

Infinitene is an infinity-shaped polycyclic aromatic hydrocarbon made of 12 consecutively fused benzene rings, first reported in 2021 and named Molecule of the Year by Chemical & Engineering News.

Oct 21, 2026

Naphtalene

Naphtalene (naphthalene, C10H8, CAS 91-20-3) is the simplest polycyclic aromatic hydrocarbon, a mothball-scented white solid made from coal tar and petroleum and used mainly to make phthalic anhydride.

Naphthalene

Naphthalene, also known as tar camphor or white tar, is a white crystalline aromatic hydrocarbon from coal tar, best known as the active ingredient of mothballs.

Olympicene

Olympicene is a polycyclic aromatic hydrocarbon, C₁₉H₁₂, whose five fused rings resemble the Olympic rings; it was first synthesized and imaged in 2012 by the University of Warwick and IBM Research – Zurich.

Phenanthrene

Phenanthrene is a polycyclic aromatic hydrocarbon with three benzene rings fused in an angular arrangement, isomeric with anthracene and found in coal tar from incomplete combustion.

Polycyclic aromatic hydrocarbon

Polycyclic aromatic hydrocarbons, also known as PAHs, are organic compounds made of fused benzene rings, formed by incomplete combustion; more than 100 exist, many toxic and carcinogenic.

Terphenyl

Terphenyl (C₁₈H₁₄) is a hydrocarbon of three linked benzene rings, existing as ortho, meta, and para isomers and used as a high-temperature heat-transfer fluid and nuclear reactor coolant.

Tetralin

Tetralin, also called 1,2,3,4-tetrahydronaphthalene, is a colorless liquid hydrocarbon made by hydrogenating naphthalene, used as an industrial solvent and the standard hydrogen donor solvent in direct coal liquefaction.

Triangulene

Triangulene, also called Clar's hydrocarbon, is a triangular molecule of 22 carbon atoms in six fused benzene rings, hypothesized in 1950 and first made in 2017.

Triphenylene

Triphenylene, also known as isochrysene or 9,10-benzophenanthrene, is a flat polycyclic aromatic hydrocarbon (C₁₈H₁₂) of four fused benzene rings, found in coal tar and used to make discotic liquid crystals.