Picene

Picene is a polycyclic aromatic hydrocarbon (PAH) with the chemical formula C22H14. It consists of five benzene rings fused in an angular, zigzag arrangement, a structure distinct from the linear arrangement of pentacene. Picene occurs in trace amounts in coal tar and related fossil-fuel byproducts and can be prepared commercially or synthesized for research purposes.

Physically, picene is a solid at room temperature with low volatility. It is poorly soluble in water but dissolves in many organic solvents such as benzene, toluene, and dichloromethane, where it forms crystalline materials. It is relatively stable under ambient conditions but can be oxidized under strong conditions.

In research contexts, picene is used as a model PAH in environmental, astrochemical, and materials science studies. It serves as a building block for organic semiconductors and as a component in thin-film electronics studies. Doping picene with alkali metals, notably potassium, has been reported to induce superconductivity at around 18 kelvin in some studies, though results are debated and reproducibility is an area of ongoing work.

Safety considerations reflect the broader family of PAHs: picene and related compounds can be hazardous and may pose mutagenic or carcinogenic risks with prolonged exposure. Appropriate handling and waste disposal procedures should be followed.

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