Studying Natural Buckyballs and Buckybowls in Fossil Materials

Buckyballs (fullerenes) were first reported over 30 years ago, but still little is known regarding their natural occurrence, since they have so far only been found at sites of high-energy incidents, such as lightning strikes or meteor impacts, but have not been reported in low-energy materials like fossil fuels. Using ultrahigh-resolution mass spectrometry, a wide range of fullerenes from C₃₀ to C₁₁₄ was detected in the asphaltene fraction of a heavy crude oil, together with their building blocks of C_10n H₁₀ stoichiometry. High-level DLPNO-CCSD(T) calculations corroborate their stability as spherical and hemispherical species. Interestingly, the maximum intensity of the fullerenes was found at C₄₀ instead of the major fullerene C₆₀ . Hence, experimental evidence supported by calculations show the existence of not only buckyballs but also buckybowls as 3-dimensional polyaromatic compounds in fossil materials.