Probing thymine with laser ablation molecular beam Fourier transform microwave spectroscopy

Area of Science:

• Chemistry
• Spectroscopy
• Molecular structure determination

Background:

• Thymine exists in various tautomeric forms.
• Understanding tautomer stability is crucial in molecular biology and chemistry.
• Previous studies have suggested the presence of the diketo form, but definitive gas-phase evidence was lacking.

Purpose of the Study:

• To unambiguously identify and characterize the diketo tautomer of thymine in the gas phase.
• To determine the precise molecular structure of the gas-phase diketo thymine.
• To provide experimental evidence for the existence of this specific tautomer under isolated conditions.

Main Methods:

• Utilized laser ablation to generate gaseous thymine molecules.
• Employed molecular beam Fourier transform microwave spectroscopy for high-resolution spectral analysis.
• Combined laser ablation with microwave spectroscopy to probe molecular structure and identify tautomers.

Main Results:

• Provided unambiguous experimental evidence for the presence of the diketo form of thymine in the gas phase.
• Successfully obtained and analyzed the rotational spectrum of the diketo thymine tautomer.
• Determined key structural parameters of the diketo thymine molecule in the gas phase.

Conclusions:

• The diketo tautomer of thymine is present and stable in the gas phase.
• Laser ablation coupled with microwave spectroscopy is a powerful technique for studying tautomers of biomolecules.
• The structural data obtained provides insights into the intrinsic properties of thymine tautomers.