"The Rotational Analyses Of 2-cyanopyrimidine (<span Class=""roman"">c</span>_{<span Class=""roman"">5</span>}<span Class=""roman"">h</span>_{<span Class=""roman"">3</span>}<span Class=""roman"">n</span>_{<span Class=""roman"">3</span>}) And 2-"

Smith, Houston H.

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https://hdl.handle.net/2142/111603 Copy

Description

Title

"The Rotational Analyses Of 2-cyanopyrimidine (c₅h₃n₃) And 2-"

Author(s)

Smith, Houston H.

Contributor(s)

• McMahon, Robert J.
• Woods, R. Claude
• Esselman, Brian J.

Issue Date

2021-06-24

Keyword(s)

Rotational structure/frequencies

Abstract

2-Cyanopyrimidine and 2-cyanopyrazine are attractive molecules for interstellar detection via radioastronomy because they are the pyrimidine and pyrazine analogs of the detected interstellar molecule, benzonitrile, and have substantial dipole moments ($\mu$ $_{a}$ = 6.47 D and $\mu$ $_{a}$ = 4.22 D, respectively). In the present work, we have analyzed and assigned the rotational spectrum of 2-cyanopyrimidine (\chem{C_5H_3N_3}) and 2-cyanopyrazine (\chem{C_5H_3N_3}) for the first time. Using data in the 130 – 360 GHz frequency region, the vibrational ground states of 2-cyanopyrimidine and 2-cyanopyrazine have been least-squares fit to partial octic, distorted-rotor Hamiltonians (N$_{lines}$ $\sim$ 4000, $\sigma$ = 40 kHz, and N$_{lines}$ $\sim$ 3900, $\sigma$ = 39 kHz, respectively). The resulting spectroscopic constants are sufficient for spectral prediction outside of the studied frequency range and enable, for the first time, radioastronomical searches for these molecules. Work currently continues on the least-squares fit of the Coriolis-coupled dyad of the two lowest-energy vibrationally excited states for each molecule. The progression of each least-squares fit will be presented along with a comparison between the two isomers. The complete analysis of these states is expected to yield a highly precise energy separation between these vibrationally excited states, along with an interesting comparison to the analogous dyads of benzonitrile and the cyanopyridines.

Publisher

International Symposium on Molecular Spectroscopy

Type of Resource

Text

Language

eng

Permalink

http://hdl.handle.net/2142/111603

DOI

10.15278/isms.2021.RA03

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