Revealing Internal Rotation and 14 N Nuclear Quadrupole Coupling in the Atmospheric Pollutant 4-Methyl-2-nitrophenol: Interplay of Microwave Spectroscopy and Quantum Chemical Calculations.
Shefali BawejaEleonore AntonelliSafia HussainAntonio Fernandez-RamosIsabelle KleinerHa Vinh Lam NguyenM Eugenia SanzPublished in: Molecules (Basel, Switzerland) (2023)
The structure and interactions of oxygenated aromatic molecules are of atmospheric interest due to their toxicity and as precursors of aerosols. Here, we present the analysis of 4-methyl-2-nitrophenol (4MNP) using chirped pulse and Fabry-Pérot Fourier transform microwave spectroscopy in combination with quantum chemical calculations. The rotational, centrifugal distortion, and 14 N nuclear quadrupole coupling constants of the lowest-energy conformer of 4MNP were determined as well as the barrier to methyl internal rotation. The latter has a value of 106.4456(8) cm -1 , significantly larger than those from related molecules with only one hydroxyl or nitro substituent in the same para or meta positions, respectively, as 4MNP. Our results serve as a basis to understand the interactions of 4MNP with atmospheric molecules and the influence of the electronic environment on methyl internal rotation barrier heights.
Keyphrases
- molecular dynamics
- particulate matter
- mass spectrometry
- density functional theory
- liquid chromatography
- high resolution
- monte carlo
- tandem mass spectrometry
- high performance liquid chromatography
- single molecule
- room temperature
- blood pressure
- gas chromatography
- heart failure
- oxidative stress
- air pollution
- replacement therapy
- solid state
- carbon dioxide
- ms ms
- atrial fibrillation
- smoking cessation
- quantum dots