Gas-Phase Electronic Absorption Spectra of Deuterated Linear Seven-Carbon Radicals

Rotationally resolved gas-phase absorption spectra of partially and fully deuterated linear seven-carbon chain radicals are presented in this article. The carbon-based molecules are generated in a supersonically expanding planar plasma by discharging a gas mixture of acetylene and deuterium-enriched acetylene in helium and argon. Spectra are recorded in direct absorption using cavity ring-down spectroscopy. The rotational analyses of the present experimental spectra allow to determine both ground and excited state rotational constants, as well as the upper state band origins of the two deuterated species.