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Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
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High-Resolution Far-Infrared Spectroscopy of N-Substituted Two-Ring Polycyclic Aromatic Hydrocarbons: An Extended
S Gruet1,2, O Pirali1,2, M Goubet3
1AILES beamline Synchrotron SOLEIL, L'Orme des Merisiers , 91190 Saint-Aubin, France.
The Journal of Physical Chemistry. A
|December 15, 2015
Summary
High-resolution spectroscopy of N-substituted polycyclic aromatic hydrocarbons (PAHs) in the far-infrared region provides accurate rotational energy levels. This study analyzes several N-substituted two-ring PAHs using FTIR and millimeter-wave spectroscopy.
Area of Science:
- Molecular spectroscopy
- Physical chemistry
- Astrophysics
Background:
- Polycyclic aromatic hydrocarbons (PAHs) and their nitrogen-substituted derivatives are crucial molecules in interstellar chemistry.
- High-resolution spectroscopy is essential for characterizing these large molecules in various environments.
Purpose of the Study:
- To report the observation and analysis of far-infrared spectra for several N-substituted two-ring PAHs.
- To accurately determine rotational energy levels in ground and excited vibrational states.
- To complement experimental data with theoretical calculations for structural insights.
Main Methods:
- Synchrotron-based Fourier transform infrared (FTIR) spectroscopy in the far-infrared region (<850 cm⁻¹).
- Millimeter and submillimeter wave spectroscopy for pure rotational transitions.
- Anharmonic Density Functional Theory (DFT) calculations for rotational and vibrational parameters.
Main Results:
- Observation and analysis of far-infrared spectra for quinoline, isoquinoline, quinoxaline, quinazoline, [1,5]-naphthyridine, [1,6]-naphthyridine, and indole.
- Accurate determination of rotational energy levels in the ground and low-lying vibrational states.
- DFT calculations supported experimental analysis and provided equilibrium structure estimates.
Conclusions:
- The combined spectroscopic and computational approach provides a comprehensive understanding of N-substituted PAHs.
- Accurate spectroscopic parameters are crucial for identifying these molecules in astronomical observations.
- This study advances the characterization of complex organic molecules in various chemical environments.
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