Preparation and characterisation of C119

Structural and electron properties of the highest epoxygenated fullerene C60O30, a DFT study

“…The free molecule C 60 was firstly calculated at HF/STO-3G (the lowest frequency 302.22 cm À1 ) and the final B3LYP/6-31G(d) gave bond lengths 1.395 and 1.454 Å , respectively, for the [6,6] and [5,6] bonds, which agrees satisfactorily with the measured values [24] as well as the results of the previous highest level calculations, MP2 with triple j plus polarization basis set [25]. Our experience of theoretical calculations on C 60 related derivatives [26][27][28][29][30] also indicate that DFT is a very successful method for studying fullerene compounds.…”

“…For instance, electrochemically active films can be grown on electrode surfaces upon reduction of C 60 O [4]. Fullerene dimer oxides have also caught the attentions, being the precursors for odd numbered all carbon fullerene dimers such as C 119 [5] or methylene-bridged C 60 dimers [6]. Since the fullerene oxides were first found in the carbon soot generated by graphite vaporization during the bulk preparation of fullerenes [7,8], C 60 O n had been synthesized by various techniques such as photooxygenation, electrochemical oxidation, ozonization, epoxidation and other experimental methods [9][10][11][12][13][14][15][16].…”

“…Since the fullerene oxides were first found in the carbon soot generated by graphite vaporization during the bulk preparation of fullerenes [7,8], C 60 O n had been synthesized by various techniques such as photooxygenation, electrochemical oxidation, ozonization, epoxidation and other experimental methods [9][10][11][12][13][14][15][16]. Detailed experimental works [9,12] on the synthesis and characterization of C 60 O suggested that it had two stable isomers; i.e., an epoxide structure with C 2v symmetry (the closed [6,6] pattern) and an ether structure with Cs ( [5,6]-open oxidoannulene) symmetry, respectively. Systematic researches including isolation, ultraviolet visible UV-vis spectra, 13 C-nuclear magnetic resonance NMR spectra characterization and single-crystal analysis on C 60 O 2 revealed that this dioxide was a fullerene diepoxide with both oxygen atoms positioned over [6,6] ring junctions on a common six-membered face of the carbon cage [14].…”

“…Quantum-chemical model evaluations of thermodynamics and kinetics of oxygen atom additions to narrow nanotubes found that the enthalpically favored structures are produced by oxygen additions to the nanotube tips and the lowest energy isomer had the lowest kinetic activation barrier [19]. Xu et al [20] had investigated the rearrangement between the closed [6,6] and open [5,6] isomers of C 60 O using semiempirical AM1 and MNDO methods. Their results revealed that the interconversion of the two isomers followed a two-step pathway involving an intermediate and two transition states.…”

Negative-ion low-temperature fast-atom bombardment mass spectrometry of monomeric and dimeric [60]fullerene compounds

“…7 Thus, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) represents the only mass spectrometric technique for most of the dimers so far. 4,[8][9][10][11][12][13] However, MALDI-TOFMS exhibits limitations in the case of the rather unstable C 120 5,6 and it does not provide the unambigous identification of C 120 OS 13 because this cannot be distinguished from C 120 O 3 under these conditions.Good solubility of the sample in the matrix is a prerequisite for FAB-MS. [17][18][19][20] Consequently, the problems with FAB-MS arise from the extremely low solubility of the [60]fullerene dimers in conventional FAB matrices. Recently, a technique was introduced which employs volatile solvents, e.g.…”