Detection of the aromatic molecule benzonitrile (c-C6H5CN) in the interstellar medium

  title={Detection of the aromatic molecule benzonitrile (c-C6H5CN) in the interstellar medium},
  author={Brett A. McGuire and Andrew M. Burkhardt and Sergei Kalenskii and Christopher N. Shingledecker and Anthony J. Remijan and Eric Herbst and Michael C. McCarthy},
  pages={202 - 205}
A specific interstellar aromatic molecule Aromatic molecules such as polycyclic aromatic hydrocarbons (PAHs) are known to exist in the interstellar medium owing to their characteristic infrared emission features. However, the infrared emission only indicates the general class of molecule, and identifying which specific molecular species are present is difficult. McGuire et al. used radio astronomy to detect rotational transitions of benzonitrile emitted from a well-known nearby cloud of… 

Detecting the building blocks of aromatics

Benzonitrile likely forms in the reaction of CN with benzene; from its observation, it is therefore possible to estimate the abundance of benzene itself; and on page 202 of this issue, McGuire et al. (3) report the detection of benzonitriel with radio telescopes.

Molecular dynamics reveals formation path of benzonitrile and other molecules in conditions relevant to the interstellar medium

This study investigates how small aromatic molecules and aromatic nitrogen heterocycles are formed from van der Waals clusters upon ionization, and shows that the large amount of energy available to the system after ionization can lead to barrier crossing and the formation of complex molecules.

Discovery of the Pure Polycyclic Aromatic Hydrocarbon Indene (c-C9H8) with GOTHAM Observations of TMC-1

Polycyclic aromatic hydrocarbons (PAHs) have long been invoked in the study of interstellar and protostellar sources, but the unambiguous identification of any individual PAH has proven elusive until

Polycyclic aromatic hydrocarbon growth in a benzene discharge explored by IR-UV action spectroscopy

Infrared signatures of polycyclic aromatic hydrocarbons (PAHs) are detected towards many phases of stellar evolution. PAHs are major players in the carbon chemistry of the interstellar medium,

Low-temperature gas-phase formation of indene in the interstellar medium

Through extensive structural reorganization of the carbon backbone, the incorporation of a five-membered ring may eventually lead to three-dimensional PAHs such as corannulene along with fullerenes (C60, C70), thus offering a new concept on the low-temperature chemistry of carbon in the authors' galaxy.

Hydrogenation of small aromatic heterocycles at low temperatures

The recent wave of detections of interstellar aromatic molecules has sparked interest in the chemical behavior of aromatic molecules under astrophysical conditions. In most cases, these detections

Aromatics and Cyclic Molecules in Molecular Clouds: A New Dimension of Interstellar Organic Chemistry.

Astrochemistry lies at the nexus of astronomy, chemistry, and molecular physics. On the basis of precise laboratory data, a rich collection of more than 200 familiar and exotic molecules have been

Polycyclic aromatic hydrocarbon formation chemistry in a plasma jet revealed by IR-UV action spectroscopy

This experiment provides evidence of the formation of larger PAHs containing up to four cyclic rings in the gas phase originating from a non-radical PAH molecule as a precursor, uncovering diacetylene radical addition as formation mechanism.

Polyacenes and diffuse interstellar bands

The identification of the carriers of the diffuse interstellar bands (DIBs) remains to be established, with the exception of five bands attributed to C60+, although it is generally agreed that DIB

Far-IR and UV spectral signatures of controlled complexation and microhydration of the polycyclic aromatic hydrocarbon acenaphthene.

This work provides UV and far-infrared ion dip spectra of homogeneous PAH multimers and their hydrated clusters and presents microhydrated PAH complexes up to the third order, where it is shown that the water clusters are locked with little perturbation on the different PAH platforms.



Formation of benzene in the interstellar medium

It is demonstrated in crossed molecular beam experiments combined with electronic structure and statistical calculations that benzene (C6H6) can be synthesized via the barrierless, exoergic reaction of the ethynyl radical and 1,3-butadiene, under single collision conditions.

Interstellar Polycyclic Aromatic Hydrocarbon Molecules

Large polycyclic aromatic hydrocarbon (PAH) molecules carry the infrared (IR) emission features that dominate the spectra of most galactic and extragalactic sources. This review surveys the observed

Reaction dynamics in astrochemistry: low-temperature pathways to polycyclic aromatic hydrocarbons in the interstellar medium.

Investigations suggest that in the hydrocarbon reactant, the vinyl-type group must be in conjugation with a -C≡CH or -HC=CH2 group to form a resonantly stabilized free radical intermediate, which eventually isomerizes to a cyclic intermediate followed by hydrogen loss and aromatization (PAH formation).

A study of interstellar aldehydes and enols as tracers of a cosmic ray-driven nonequilibrium synthesis of complex organic molecules

It is shown in a combined experimental, computational, and astrochemical modeling study that interstellar aldehydes and enols act as key tracers of a cosmic-ray-driven nonequilibrium chemistry leading to complex organics even deep within low-temperature interstellar ices at 10 K.

Rotational Spectra of Small PAHs: Acenaphthene, Acenaphthylene, Azulene, and Fluorene

Pure rotational spectra of four small polycyclic aromatic hydrocarbons have been observed by Fourier transform microwave spectroscopy of a molecular beam in the frequency range from 7 to 37 GHz.

Search for corannulene (C20H10) in the Red Rectangle

Polycyclic Aromatic Hydrocarbons (PAHs) are widely accepted as the carriers of the Aromatic Infrared Bands (AIBs), but an unambiguous identification of any specific interstellar PAH is still missing.

Structure-dependent Photostability of Polycyclic Aromatic Hydrocarbon Cations: Laboratory Studies and Astrophysical Implications

Following a previous experimental study of the photostability of a series of polycyclic aromatic hydrocarbons (PAHs) this work extends to irregularly shaped PAHs, methyl-substituted PAHs, and related

Interstellar chemistry: a strategy for detecting polycyclic aromatic hydrocarbons in space.

The high-resolution rotational spectrum of corannulene has been obtained by Fourier transform microwave spectroscopy, and the dipole moment of this exceptionally polar PAH has been measured by exploiting the Stark effect.

Top-down formation of fullerenes in the interstellar medium.

This model predicts absolute abundances of C60 are up to several 10-4 of the elemental carbon, which is consistent with observational studies, and according to this model, once formed, C60 can survive much longer than other fullerenes in highly irradiated environments.