title: Photochemical and photophysical properties of three carbon-bridged fullerene dimers: C121 (I, II, III).
abstract: The photochemical and photophysical properties of the three C121 isomers (I, II, III) were investigated with MADLI-TOF-MS, UV-vis spectra, fluorescence spectra, absorption spectra of their DMA complexes, and theoretical calculations. The three isomers of C121 (I, II, III) have different stabilities under laser irradiation, but isomer I and isomer II show good stability against the heat-induced conversion between different isomers: No conversion between the isomers was found after heating the mixture of isomer I and isomer II at 353 K for 12 h in Ar atmosphere. The results of UV-vis absorption and fluorescence spectra indicate that interactions between two C60 moieties of C60=C=C60 in the ground and singlet states are not significant, C121 (I, II, III) behaves as an electron-acceptor similar to C60. These indicate that the formation of the fullerene chain structure (e.g., C60=C=C60) does not disturb the photochemical and photophysical properties of the C60 monomer itself, even that the properties were enhanced by the formation of the polymer. This is significant for the C60 polymer in photochemical or photoelectronic applications in which C60=C=C60 can be an excellent basic unit of polymers.
authors.affiliation: Laboratory for Bio-Environmental Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Science, Beijing 100049, China.
authors.forename: Tongxiang
authors.initials: T
authors.lastname: Ren
authors.forename: Baoyun
authors.initials: B
authors.lastname: Sun
authors.forename: Zhenling
authors.initials: Z
authors.lastname: Chen
authors.forename: Li
authors.initials: L
authors.lastname: Qu
authors.forename: Hui
authors.initials: H
authors.lastname: Yuan
authors.forename: Xingfa
authors.initials: X
authors.lastname: Gao
authors.forename: Shukuan
authors.initials: S
authors.lastname: Wang
authors.forename: Rui
authors.initials: R
authors.lastname: He
authors.forename: Feng
authors.initials: F
authors.lastname: Zhao
authors.forename: Yuliang
authors.initials: Y
authors.lastname: Zhao
authors.forename: Zhongshi
authors.initials: Z
authors.lastname: Liu
authors.forename: Xiping
authors.initials: X
authors.lastname: Jing
mesh_terms: D002244:Carbon / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D019281:Dimerization; D004583:Electrons; D037741:Fullerenes / Q000737:chemistry*; D007536:Isomerism; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010777:Photochemistry; D011108:Polymers / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013056:Spectrophotometry, Ultraviolet; D013816:Thermodynamics
chemical_list: D037741:Fullerenes; D011108:Polymers; D002244:Carbon