title: Semiconducting single crystals comprising segregated arrays of complexes of C60.
abstract: Although pristine C60 prefers to adopt a face-centered cubic packing arrangement in the solid state, it has been demonstrated that noncovalent-bonding interactions with a variety of molecular receptors lead to the complexation of C60 molecules, albeit usually with little or no control over their long-range order. Herein, an extended viologen-based cyclophane—ExBox2(4+)—has been employed as a molecular receptor which, not only binds C60 one-on-one, but also results in the columnar self-assembly of the 1:1 inclusion complexes under ambient conditions. These one-dimensional arrays of fullerenes stack along the long axis of needle-like single crystals as a consequence of multiple noncovalent-bonding interactions between each of the inclusion complexes. The electrical conductivity of these crystals is on the order of 10(-7) S cm(-1), even without any evacuation of oxygen, and matches the conductivity of high-quality, unfunctionalized C60-based materials that typically require stringent high-temperature vaporization techniques, along with the careful removal of oxygen and moisture, prior to measuring their conductance.
authors.affiliation: Departments of †Chemistry and ‡Materials Science and Engineering, Northwestern University , 2145 Sheridan Road, Evanston, Illinois 60208, United States.
authors.forename: Jonathan C
authors.initials: JC
authors.lastname: Barnes
authors.forename: Edward J
authors.initials: EJ
authors.lastname: Dale
authors.forename: Aleksandrs
authors.initials: A
authors.lastname: Prokofjevs
authors.forename: Ashwin
authors.initials: A
authors.lastname: Narayanan
authors.forename: Ian C
authors.initials: IC
authors.lastname: Gibbs-Hall
authors.forename: Michal
authors.initials: M
authors.lastname: Juríček
authors.forename: Charlotte L
authors.initials: CL
authors.lastname: Stern
authors.forename: Amy A
authors.initials: AA
authors.lastname: Sarjeant
authors.forename: Youssry Y
authors.initials: YY
authors.lastname: Botros
authors.forename: Samuel I
authors.initials: SI
authors.lastname: Stupp
authors.forename: J Fraser
authors.initials: JF
authors.lastname: Stoddart
mesh_terms: D003460:Crystallization; D018360:Crystallography, X-Ray; D037741:Fullerenes / Q000737:chemistry*; D012666:Semiconductors
chemical_list: D037741:Fullerenes; C069837:fullerene C60