An 18-member carbon ring

Abstract

Surface Chemistry Carbon's allotropes include molecular species such as C60 and C70 fullerenes. Kaiser et al. now report the assembly of a large carbon ring, cyclo[18]carbon, from organic precursors whose reactivity was controlled by adsorbing them on a sodium chloride surface at 5 kelvin (see the Perspective by Maier). Manipulation, with an atomic force microscope tip, of a cyclocarbon oxide molecule, C24O6, led to elimination of carbon monoxide molecules and formation of the desired all-carbon ring. High-resolution imaging revealed alternating single and triple bonds versus an all-double-bond structure. Science , this issue p. [1299][1]; see also p. [1245][2] [1]: /lookup/doi/10.1126/science.aay1914 [2]: /lookup/doi/10.1126/science.aay7461