Vis-Near-IR Spectroscopic and Time-Dependent DFT Study of Reduced Singly Bonded C₆₀ Species

Abstract

Reduced fullerenes and fullerene derivatives exhibit intense absorptions in the vis-near-IR (vis-NIR) region. The absorptions are sensitive toward the addition pattern, number of addends, and oxidation state of the fullerene species and are used as an important benchmark for identifying anionic fullerene species. Similar absorptions are also shown for the reduced singly bonded C60 species, which are electronically different from reduced fullerene derivatives. However, much less work has been carried out on the vis-NIR spectroscopic study of the anionic singly bonded C60 species, likely due to the difficulty in controlled production of these species. Herein, we report the vis-NIR spectroscopic study of the mono- and dianions of the singly bonded C60 species (RC60(-), R(-)C60(-), and RC60(2-•)), which are selectively generated by controlled-potential bulk electrolysis (CPE) of the singly bonded C60 dimer and C60 oxazolino heterocycles. Time-dependent density functional theory (TD-DFT) calculations were performed to rationalize the experimental results.

Dual-Readout Tyrosinase Activity Assay Facilitated by a Chromo-Fluorogenic Reaction between Catechols and Naphthoresorcin

“…On the basis of the optimized structures, the absorbance and fluorescence emission spectra were calculated by TD-DFT at the B3LYP level with the 6-311G­(d) basis set. The TD-B3LYP is a feasible method and is widely applied in exploring the calculated spectra . All the calculations were performed with the Gaussian 09 software package.…”

“…The TD-B3LYP is a feasible method and is widely applied in exploring the calculated spectra. 30 All the calculations were performed with the Gaussian 09 software package. The dimensional plots of the molecular orbital were generated with the Gauss View program (Gaussian, Inc. Pittsburgh, PA).…”

Synthesizing 1,23-C60 Adducts with Improved Efficiency: A Type of Stable and Highly Soluble C60 Derivatives

“…Strong absorptions appeared gradually at 972 and 631 nm after C 60 was added into the mixture of 1a and TBAOH, and they remained stable until the mixture was quenched with I 2 . The pattern of the absorptions is essentially identical to that of RC 60 – (R = t -Bu: 995 and 656 nm; octynyl: 990 and 650 nm; Bn: 993 and 658 nm) with the appearance of two strong peaks except for a blueshift of about 20 nm, which is likely caused by the difference of addends, indicating that RC 60 – was involved during the formation of the 1,23- and 1,7-adducts.…”

Copper-Catalyzed Aerobic Oxidative Reaction of C60 with Aliphatic Primary Amines and CS2

“…In principle, the dithiocarbamic acid may undergo nucleophilic addition to C 60 through the anionic sulfur atom in a manner similar to the addition of anionic oxygen nucleophile. 24a However, such addition would result in anionic singly bonded fullerene species that have near-IR absorptions different from that of C 60 •− , 36 which was not observed by the in situ spectroscopy. Control experiment with TEMPO (2 equiv) severely prohibited the formation of the product (entry 15, Table 1), implying that the reaction involved radical intermediates.…”