C30H18

C30H18 is a molecular formula that represents a hydrocarbon consisting of thirty carbon atoms and eighteen hydrogen atoms. The formula reflects a highly unsaturated structure and is typically associated with polycyclic aromatic hydrocarbons (PAHs). The degree of unsaturation for C30H18 is calculated using the formula 2C + 2 – H (divided by two for rings and double bonds), which yields 12; therefore the molecule contains at least twelve rings or double bonds.

Because several distinct connectivity patterns of the 30 carbon atoms can satisfy the same empirical formula, C30H18 can correspond to numerous isomeric species. Common classes of isomers include those with linear arrangements of fused aromatic rings, such as extended acenes, or those with condensed ring systems like phenanthrene derivatives. In laboratory settings, the formation of such isomers can be controlled by synthetic methods that dictate the fusion pattern of the aromatic systems.

The prevalence of aromatic rings in C30H18 structures gives rise to characteristic absorption in the ultraviolet and visible spectra, making these molecules useful as chromophores in organic electronics and dye chemistry. In some contexts, large PAHs with the formula C30H18 have been investigated for their potential as organic semiconductors due to delocalized π‑electron systems that facilitate charge transport.

Natural occurrences of C30H18 compounds are relatively rare; most are produced through synthetic organic chemistry. However, analogue molecules derived from this core structure appear in the analysis of interstellar carbonaceous dust and in the spectra of combustion products, indicating the importance of large aromatic hydrocarbons in diverse chemical environments.

The study of C30H18 and its isomers contributes to a deeper understanding of aromatic stability, electronic properties of extended conjugated systems, and the development of functional materials for optoelectronic applications.