Rotationally resolved absorption spectra of the e A 1 P u — e X 1 R þ g origin band of the tricarbon molecule (C 3) are reported for 12 C 3 and its 13 C-substitued isotopologues. The 4051 Å electronic transition, also identified in cometary tails and in translucent interstellar clouds, has been measured using cavity ring-down spec-troscopy and a supersonically expanding planar plasma. Previous ...

We have investigated the synthesis of the simplest amino acid, glycine, by Galactic cosmic-ray particles in extraterrestrial ices. Laboratory experiments combined with electronic structure calculations showed that a methylamine molecule [CH3NH2(X 1A0)] can be dissociated through interaction with energetic electrons in the track of a cosmicray particle to form atomic hydrogen and the radicals CH...

We present the first results of an experimental method (jet expansion followed by laser induced fluorescence) that collects absorption spectra of cold, gas-phase isolated species. This method, closely simulating interstellar conditions, is a powerful tool to assert diffuse interstellar bands (DIB) identification. It only requires the species studied to be fluorescent. This latter condition is f...

Even though quartic force fields (QFFs) and highly accurate coupled cluster computations describe the OCHCO(+) cation at equilibrium as a complex between carbon monoxide and the formyl cation, two notable and typical interstellar and atmospheric molecules, the prediction from the present study is that the equilibrium C(∞v) structure is less relevant to observables than the saddle-point D(∞h) st...

Aims. Aminoalcohol molecules such as alpha-aminoethanol NH2CH(CH3)OH may be aminoacid precursors. We attempt to characterize and detect this kind of molecules which is important to establish a possible link between interstellar molecules and life as we know it on Earth. Methods. We use Fourier transform infrared (FTIR) spectroscopy and mass spectrometry to study the formation of alphaaminoethan...

The OH+ ions are widespread in the interstellar medium and play an important role in the interstellar chemistry as they act as precursors to the H2O molecule. Accurate determination of their abundance rely on their collisional rate coefficients with atomic hydrogen and electrons. In this paper, we derive OH+–H fine and hyperfine-resolved rate coefficients by extrapolating recent quantum wave pa...

Based on theoretical spectra computed using Density Functional Theory we study the properties of Polycyclic Aromatic Hydrocarbons (PAH). In particular bin-average PAH molecules with varying number carbons investigate how intensity mid-infrared emission bands, 3.3, 6.2, 7.7 and 11.3 microns, respond to changes in carbons, charge molecule, hardness radiation field that impinges molecule. We confi...

The formation, chemical, and thermal processing of complex organic molecules (COMs) is currently a topic of much interest in interstellar chemistry. The isomers glycolaldehyde, methyl formate, and acetic acid are particularly important because of their role as pre-biotic species. It is becoming increasingly clear that many COMs are formed within interstellar ices which are dominated by water. H...