physics4me

The rich molecular structures of polycyclic aromatic hydrocarbons — essentially planar flakes of fused benzene rings — and their fullerene cousins are revealed through their vibrational and electronic spectra.

In this artistic impression, large polycyclic aromatic hydrocarbon (PAH) molecules exposed to the strong radiation field of a star first lose all their peripheral hydrogen atoms (white atoms, top right) and are transformed into small graphene flakes whose fragile, dangling carbon rings at the corners break off. That degradation is then followed by the loss of carbon atoms. The loss creates pentagons (red) in the dehydrogenated PAH molecule, which bends the structure out of the plane and culminates in the formation of a C60 fullerene

A. Candian, J. Zhen, A.G.G.M. Tielens
Over the past 20 years, ground- and space-based observations have revealed that the universe is filled with molecules. Astronomers have identified nearly 200 types of molecules in the interstellar medium (ISM) of our galaxy and in the atmospheres of planets; for the full list, see http://www.astrochymist.org. Molecules are abundant and pervasive, and they control the temperature of interstellar gas. Not surprisingly, they directly influence such key macroscopic processes as star formation and the evolution of galaxies.
read more at https://arxiv.org/ftp/arxiv/papers/1908/1908.05918.pdf