Monday, 29 May 2017: 11:00
Churchill A2 (Hilton New Orleans Riverside)
We recently reported the occurrence and crystal structures of two, concomitant, rotationally disordered polymorphs of C60•2S8 at room temperature, the α- and γ- forms, and their crystal-to crystal transformations to fully ordered polymorphs named β- and δ- C60•2S8, respectively, at low temperatures.1 At 90 K, certain ball---ball centroids of both forms are relatively close, the shortest being 9.881 Å and 9.855 Å, respectively. Polymerization of C60 has received attention over the years in quest of interesting properties. These studies have primarily utilized powdered C60. We were curious to see happens to C60 under high pressure in a crystalline, binary phase such as with S8, and if crystal-to-crystal transformations would occur. Possibly S8would catalyze polymerization and help to prevent fullerene collapse, and orientational ordering would occur. High pressure measurements have been carried out at the Advanced Light Source, Lawrence Berkeley National Lab, and our results will be summarized.
1Ghiassi, et al., Cryst. Growth Des. 2015, 15, 404.