The crystal structure of RbC_60, determined by Peter Stephens and coworkers from powder diffraction data, based on a model suggested by Laszlo Mihaly and coworkers.

When fullerenes first came on the scene, there was considerable speculation about how they might be threaded together to make a "pearl necklace" polymer. Following their determination of the atomic structure of superconducting alkali fullerides, Mihaly and Stephens were investigating the electronic and structural properties of various fullerene materials with their students and collaborators, when they made the unexpected discovery that C_60 will polymerize spontaneously if catalyzed by extra electrons.