Topic
Oxocarbon
About: Oxocarbon is a research topic. Over the lifetime, 109 publications have been published within this topic receiving 1529 citations. The topic is also known as: carbon oxide.
Papers published on a yearly basis
Papers
TL;DR: Localized orbital contributions to the nucleus-independent chemical shifts (NICS) allow pi effects to be disected from the sigma single bonds and other influences and the dissociation energies of all the neutral oxocarbons, C(n)()O(n)(), are highly exothermic.
Abstract: Assessment of the cyclic electron delocalization of the oxocarbon dianions, CnOn2- and their neutral counterparts CnOn (n = 3−6), by means of structural, energetic, and magnetic criteria, shows that C3O32- is doubly aromatic (both σ and π cyclic electron delocalization), C4O42- is moderately aromatic, but C5O52-, as well as C6O62-, are less so. Localized orbital contributions, computed by the individual gauge for localized orbitals method (IGLO), to the nucleus-independent chemical shifts (NICS) allow π effects to be disected from the σ single bonds and other influences. The C−C(π) contribution to (NICS(0,π) (i.e., at the center of the ring) in oxocarbon dianions decreases with ring size but shows little ring size effect at points 1.0 A above the ring. On the basis of the same criteria, C4O4 exhibits cyclic electron delocalization due to partial occupancy of the σ CC bonds. However, the dissociation energies of all the neutral oxocarbons, CnOn, are highly exothermic.
128 citations
Patent•
29 Apr 2008
TL;DR: In this article, the use of oxocarbon-, pseudooxocarbon and radialene compounds as doping agent for organic semiconductive matrix material, as blocker material, charge injection layer, as electrode material as well as organic semiconductor, was discussed.
Abstract: The present invention relates to oxocarbon-, pseudooxocarbon- and radialene compounds as well as to their use as doping agent for doping an organic semiconductive matrix material, as blocker material, as charge injection layer, as electrode material as well as organic semiconductor, as well as electronic components and organic semiconductive materials using them.
90 citations
TL;DR: In this article, the formation of the new spectrum as CO is dosed is accompanied by a simultaneous decrease in the absorption due to surface states (coordinatively unsaturated surface oxide ions).
Abstract: The adsorption of carbon monoxide at room temperature on well-outgassed specimens of MgO, CaO, SrO and BaO gives rise to a strong absorption spectrum between text-decoration:overlineν= 15000 and text-decoration:overlineν= 40000 cm–1. The stronger the outgassing conditions, the more intense is the absorption which can be developed.The spectrum consists of two main envelopes, one comprising absorption at text-decoration:overlineν= 29000–40000 cm–1 and the other, more composite in character, at text-decoration:overlineν= 15000–29000 cm–1. Changes in the CO pressure affect the two spectral regions differently, showing that two different kinds of adsorbed species are involved.The formation of the new spectrum as CO is dosed is accompanied by a simultaneous decrease in the absorption due to surface states (coordinatively unsaturated surface oxide ions). The effect on the oxide absorption is more pronounced with SrO and CaO than with MgO. The bulk states are unaffected, showing that the process is entirely a surface reaction.The results are interpreted as an electron donor process in which CO accepts electrons from surface oxide ions and forms anionic clusters in the adsorbed state. The high-text-decoration:overlineν absorption (ν > 29 000 cm–1) is ascribed to the dimer (CO)2–2, and the low-text-decoration:overlineν absorption to polymeric oxocarbon anions (CO)xn, where n > 2. The latter are considered to include cyclic, resonance-stabilized structures. The reactivity of the oxide towards CO increases with increase in basic character: on the MgO surface there are relatively few sites of sufficient donor potential to react with CO, but on the more strongly basic CaO and SrO the reaction is much more extensive.
69 citations
62 citations
TL;DR: In this paper, a facile and reproducible means of producing quasi-spherical, colloidally stable gold nanoparticles (AuNPs) on the basis of rapid room-temperature mixing of aqueous solutions of HAuCl4 and a cyclic oxocarbon diacid (squaric acid, SA, croconic acid and rhodizonic acid) or ascorbic acid (AA) as dual reducing and capping agent was demonstrated.
Abstract: We demonstrate a facile and reproducible means of producing quasi-spherical, colloidally stable gold nanoparticles (AuNPs) on the basis of rapid room-temperature mixing of aqueous solutions of HAuCl4 and a cyclic oxocarbon diacid (squaric acid, SA; croconic acid, CA; or rhodizonic acid, SR) or ascorbic acid (AA) as dual reducing and capping agent Although these reducing agents generally produced larger particles than those derived from the classical Turkevich method (using citrate in boiling water) and achieved a lower nanoparticle size uniformity in our hands (ie, 304 ± 86, 331 ± 93, 299 ± 63, and 297 ± 76 nm for SA, AA, CA, and SR, respectively, compared with 158 ± 37 nm for citrate), the method is versatile and exceptionally convenient as fairly monodisperse AuNPs can be made “on-demand” within seconds by simple mixing in the absence of heating A preliminary investigation into the effects of reaction parameters, such as synthesis temperature and the molar ratio of reducing agent to HAuCl4
60 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 3 |
| 2020 | 2 |
| 2019 | 4 |
| 2018 | 4 |
| 2017 | 2 |
| 2016 | 10 |