Astrochemistry

Observation Of Spontaneous N-bearing PAH Formation Using Ion Trap: A New Formation Pathway In The Interstellar Medium

By Keith Cowing
Press Release
May 16, 2026
Filed under , , , , , , , ,
Observation Of Spontaneous N-bearing PAH Formation Using Ion Trap: A New Formation Pathway In The Interstellar Medium
Schematic drawing of the modified 22-pole radio frequency ion trap setup. The ions are produced between the first two plates of the ion guide by electron impact ionization and repelled towards the QMS-1. Mass-selected ions are injected into the 22-pole trap. The trap is equipped with neutral and pulsed buffer gas input ports. A neutral density measurement gauge (Pfeiffer CMR 375) is also connected to the trap volume. After a specified trapping time, the ions are mass-analyzed by QMS-2 and counted in the CEM detector. — astro-ph.GA

Nitrogen-bearing polycyclic aromatic hydrocarbons (N-PAHs) are key precursors to complex organic molecules in both the interstellar medium and the nitrogen-rich planetary atmospheres.

Despite the recent detections of nitrogen-functionalized astromolecules, their formation pathways remain an open question. The discrepancies between their predicted and observed abundances point to unknown mechanism that govern their evolution in the astrophysical environments.

Employing an ion trap technique and electronic structure calculations, we unravel multiple barrier-less reactions between gas-phase pyrimidine cations (C4H4N+2) and acetylene (C2H2) which form an hitherto unreported endocyclic- N-PAHs (C8H7N+2).

The present measurements on reactions involving a double-nitrogen subsituted aromatic heterocycle have implications to the astrochemistry of both the Titan’s atmosphere and interstellar medium.

Siddhartha S. Payra, Pratikkumar Thakkar, Shiv Gupta, Ruth Ann Mathews, Yash Lenka, Saurav Dutta, Nihar Ranjan Behera, Krishna R. Nandipati, G. Aravind

Subjects: Astrophysics of Galaxies (astro-ph.GA); Chemical Physics (physics.chem-ph)
Cite as: arXiv:2605.14424 [astro-ph.GA](or arXiv:2605.14424v1 [astro-ph.GA] for this version)
https://doi.org/10.48550/arXiv.2605.14424
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Submission history
From: Siddhartha S. Payra
[v1] Thu, 14 May 2026 06:14:07 UTC (13,108 KB)
https://arxiv.org/abs/2605.14424

Astrobiology, Astrochemistry,

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