Related papers: Mapping the structural diversity of C60 carbon clu…
The detection of fullerene molecules in a variety of astrophysical environments suggests that smaller dehydrogenated carbon molecules may also be present in these sources. One of these is planar C24 which has been shown to be more stable…
Buckminsterfullerene (C60) was recently detected through its infrared emission bands in the interstellar medium (ISM), including in the proximity of massive stars, where physical conditions could favor the formation of the cationic form,…
Together with the second generation REBO reactive potential, replica-exchange molecular dynamics simulations coupled with systematic quenching were used to generate a broad set of isomers for neutral C$_n$ clusters with $n=24$, 42, and 60.…
Astronomical infrared spectral features at ~6.6, 9.8 and 20 micronm have recently been suggested as being due to the planar graphene form of C24 carbon cluster. Here we report density functional theory and coupled cluster calculations on…
Infrared emission bands with wavelengths between 3-20 {\mu}m are observed in a variety of astrophysical environments [1,2]. They were discovered in the 1970s and are generally attributed to organic compounds [3,4]. However, over 40 years of…
Although fullerenes have long been hypothesized to occur in interstellar environments, their actual unambiguous spectroscopic identification is of more recent date. C60, C70 and C60+ now constitute the largest molecular species individually…
We searched the Spitzer Space Telescope data archive for Galactic planetary nebulae (PNe), that show the characteristic 17.4 and um features due to C60, also known as buckminsterfullerene. Out of 338 objects with Spitzer/IRS data, we found…
We report a computational study of the stability and infrared (IR) vibrational spectra of neutral and singly ionised fullerene cages containing between 44 and 70 carbon atoms. The stability is characterised in terms of the standard enthalpy…
We recently identified several emission bands in the Spitzer-IRS spectrum of the unusual planetary nebula Tc 1 with the infrared active vibrational modes of the neutral fullerene species C60 and C70. Since then, the fullerene bands have…
The recent detection of fullerene (C$_{60}$) in space and the positive assignment of five diffuse interstellar bands to C$_{60}^+$ reinforce the notion that fullerene-related compounds can be efficiently formed in circumstellar envelopes…
Laboratory spectra of hydrogenated amorphous carbon (HAC) particles prepared under a variety of conditions show spectral features at 7.05, 8.5, 17.4 and 18.9 {\mu}m (1418, 1176, 575 & 529 cm-1) that have been associated with emission from…
Recent studies have confirmed the presence of buckminsterfullerene (C$_{60}$) in different interstellar and circumstellar environments. However, several aspects regarding C$_{60}$ in space are not well understood yet, such as the formation…
Small cationic fullerene fragments, produced by electron impact ionization of C60, were mass-selected and accumulated in cryogenic Ne matrixes. Optical absorption spectroscopy of these fragments with up to 18 carbon atoms revealed linear…
Detections of C60 and C70 fullerenes in planetary nebulae (PNe) of the Magellanic Clouds and of our own Galaxy have raised the idea that other forms of carbon such as hydrogenated fullerenes (fulleranes like C60H36 and C60H18), buckyonions,…
Recent Spitzer Space Telescope observations of several astrophysical environments such as Planetary Nebulae, Reflection Nebulae, and R Coronae Borealis stars show the simultaneous presence of mid-infrared features attributed to neutral…
We present seeing-limited narrow-band mid-IR GTC/CanariCam images of the spatially extended fullerene-containing planetary nebula (PN) IC 418. The narrow-band images cover the C60 fullerene band at 17.4 {\mu}m, the polycyclic aromatic…
Fullerenes are a particularly stable class of carbon molecules in the shape of a hollow sphere or ellipsoid that might be formed in the outflows of carbon stars. Once injected into the interstellar medium (ISM), these stable species survive…
It is well known since 2010 that fullerene C60 is widespread through the interstellar space. Also, it is well known that graphene is a source material for synthesizing fullerene. Here, we simply assume the occurrence of graphene in space.…
This paper is the fourth and final report on a project designed to study carbon abundances in a sample of planetary nebulae representing a broad range in progenitor mass and metallicity. We present newly acquired optical spectrophotometric…
The presence of neutral C60 fullerenes in circumstellar environments has been firmly established by astronomical observations as well as laboratory experiments and quantum-chemistry calculations. However, the large variations observed in…