Bonn 2025 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MO: Fachverband Molekülphysik
MO 20: Poster – Molecular Spectroscopy and Dynamics
MO 20.14: Poster
Mittwoch, 12. März 2025, 17:00–19:00, Tent
Probing De-excitation and Vibrational Re-Distribution Processes in Jet-Cooled N2O Using a Combination of cw-Infrared and Microwave Chirped Pulse Technique — •Jonas Bosmann, Fabian Peterß, Jan Wenske, Guido Fuchs, and Thomas Giesen — Institute of Physics, University of Kassel, Germany
Chirped pulse Fourier transform spectroscopy (CP-FT) is a sensitive and nowadays widely used method for recording gas phase spectra of molecules in the microwave (MW) and millimeter wave (mmW) range. Here, we present CP-FT supersonic beam measurements of N2O, state selectively excited by an infrared continuous wave (cw) optical parametric oscillator (OPO). The CP-FT signal of the J = 4 ← 3 transiton around 100 GHz was used to study the relaxation of vibrationally excited N2O into different vibrational levels of lower energy. Since this is to our knowledge the first CP-MW study that uses cw-laser excitation, we investigated the strength of the FID signal as a function of the infrared laser power. The collision-induced redistribution of pure rotational levels in vibrationally states and the redistribution of vibrational energy were investigated in two different jet environments, for which a slit nozzle of high collision rates and a pin-hole nozzle of low collision rates in the jet expansion were used.
Keywords: Vibrationally Excited States; Millimeter-wave Spectroscopy; Rotational Spectroscopy; Vibrational Spectroscopy; Chirped Pulse Fourier Transform