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Updated: Aug 13, 2026
08:55
High-Temperature and High-Pressure In situ Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy
Published on: October 9, 2020
High-resolution ro-vibrational and rotational spectroscopy of deuteronated formaldehyde, H2COD
Denis Comte1, Mattia Melosso2, Hunarpreet Kaur3,4
1Scuola Superiore Meridionale, Largo San Marcellino 10, 80138 Naples, Italy. d.comte@ssmeridionale.it.
Physical Chemistry Chemical Physics : PCCP
|August 12, 2026
Summary
Protonated formaldehyde isotopologue H₂COD⁺ is key for astrochemical models but hard to observe. This study provides crucial molecular data, enabling future interstellar medium searches and structural analysis.
Area of Science:
- Astrochemistry
- Molecular Spectroscopy
- Quantum Chemistry
Background:
- Protonated formaldehyde (H₂COD⁺) is predicted to be abundant in prestellar cores.
- Lack of high-resolution molecular data hinders its astronomical observation.
Purpose of the Study:
- Investigate the ro-vibrational and rotational spectra of H₂COD⁺.
- Provide accurate spectroscopic parameters for interstellar medium searches.
- Determine the equilibrium structure of protonated formaldehyde.
Main Methods:
- Cryogenic ion trap instrument at 4 K.
- Leak-out spectroscopy for ro-vibrational transitions (ν₁ band).
- Rotational-vibrational double-resonance spectroscopy for pure rotational transitions.
- High-level quantum-chemical calculations for spectral assignment.
- Simultaneous analysis of ro-vibrational and rotational data.
Main Results:
- Detected and assigned ro-vibrational transitions in the 3095–3155 cm⁻¹ region.
- Measured 36 pure rotational transitions.
- Obtained highly accurate ground state spectroscopic parameters for H₂COD⁺.
- Derived an almost complete semi-experimental equilibrium structure for protonated formaldehyde.
Conclusions:
- The obtained spectroscopic data facilitate future radio astronomical searches for H₂COD⁺.
- The study provides essential molecular data for understanding chemical evolution in prestellar cores.
- Accurate structural determination aids in refining astrochemical models.
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