PDN-FTMW spectroscopy of short lived molecules and their complexes

Abstract

Fourier-transform microwave (FTMW) spectroscopy combined with a Fabry-Perot cavity and a pulsed supersonic jet method has been shown to have fairly high sensitivity in the cm-wave region, and is now extensively used for studies of numbers of molecular complexes. Recently, we have implemented a pulsed discharge nozzle (PDN) to our FTMW spectrometer in order to produce short lived species. It was found that the method is advantageous to studies of short lived species with small rotational constants, when compared with mm- or submm-wave spectroscopy which is most popularly used for observations of pure rotational spectra of short lived species. Since the accessible rotational quantum number is lower and resolution is higher than the case of mm- or submm-wave spectroscopy, well resolved hyperfine structures are observed even for large molecules with small hyperfine splittings. Moreover, the method enable us to study molecular complexes containing such short lived species. The talk will discuss our recent results on carbon chain molecules, such as $C_{n}H, HC_{n}O, HC_{n}S$, and $C_{n}S$, a few complexes containing short lived species, as well as molecular ions.