Structure of the crystalline C60 photopolymer and the isolation of its cycloadduct components

Eva Kováts; Gábor Oszlányi; Sándor Pekker

doi:10.1021/jp051727i

Structure of the crystalline C60 photopolymer and the isolation of its cycloadduct components

J Phys Chem B. 2005 Jun 23;109(24):11913-7. doi: 10.1021/jp051727i.

Authors

Eva Kováts¹, Gábor Oszlányi, Sándor Pekker

Affiliation

¹ Research Institute for Solid State Physics and Optics, Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest, Hungary.

PMID: 16852467
DOI: 10.1021/jp051727i

Abstract

We produced C60 photopolymer in gram quantity by a new monomer recycling method and extracted its soluble components. The most abundant components, the (2 + 2) cycloadduct dimer, C120, and several oligomers were isolated by high-performance liquid chromatography (HPLC). Three different C180 isomers were identified on the basis of their formation and decomposition reactions. The crystal structure of the insoluble photopolymer is face-centered cubic (fcc) with a contracted lattice parameter relative to the pristine C60. The lattice parameter and the amounts of soluble oligomers depend on the preparation temperature. We explain this variation with a topochemical model of photopolymerization: The geometrical conditions allow the formation of only linear or planar oligomers in the triangular or square sublattices. Competing reactions in the intersecting planes prevent the formation of large oligomers. The lattice contraction is proportional to the number of cycloadduct bonds.