Alexander Fateev

ExoMol molecular line lists – XIV. The rotation–vibration spectrum of hot SO2

Sulphur trioxide (SO3) is a trace species in the atmospheres of the Earth and Venus, as well as being an industrial product and an environmental pollutant. A variational line list for 32S16O3, named UYT2, is presented containing 21 billion vibration–rotation transitions. UYT2 can be used to model infrared spectra of SO3 at wavelengths longwards of 2 μm (ν < 5000 cm−1) for temperatures up to 800 K. Infrared absorption cross-sections recorded at 300 and 500 C are used to validate the UYT2 line list. The intensities in UYT2 are scaled to match the measured cross-sections. The line list is made available in electronic form as supplementary data to this article and at www.exomol.com.

Influence of ultrasonic irradiation on ozone generation in a dielectric barrier discharge

An atmospheric pressure dielectric barrier discharge (DBD) was generated in an N2/O2 gas mixture at room temperature with and without ultrasonic irradiation to investigate ozone production. Powerful ultrasonic irradiation with the sound pressure level of approximately 150 dB into the DBD can enhance ozone production especially when the DBD was driven at a frequency of 15 kHz.

ExoMol line lists – XXIX. The rotation-vibration spectrum of methyl chloride up to 1200 K

Comprehensive rotation-vibration line lists are presented for the two main isotopologues of methyl chloride, 12CH3 35Cl and 12CH3 37Cl. The line lists, OYT-35 and OYT-37, are suitable for temperatures up to T = 1200 K and consider transitions with rotational excitation up to J = 85 in the wavenumber range 0 – 6400 cm−1 (wavelengths λ > 1.56μm). Over 166 billion transitions among 10.2 million energy levels have been calculated variationally for each line list using a new empirically refined potential energy surface, determined by refining to 739 experimentally derived energy levels up to J = 5, and an established ab initio dipole moment surface. The OYT line lists show excellent agreement with newly measured high-temperature infrared absorption cross-sections, reproducing both strong and weak intensity features across the spectrum. The line lists are available from the ExoMol database and the CDS database.