title: Electronic spectra of the MgC4H and MgC6H radicals.
abstract: Electronic transitions of the linear MgC 4H and MgC 6H radicals have been observed in the gas phase using laser-induced fluorescence spectroscopy. The species were prepared in a supersonic expansion by ablation of a magnesium rod in the presence of acetylene, diacetylene, or methane gas. The transitions were recorded in the 445-446 nm region and assigned to the A (2)Pi- X (2)Sigma (+) systems ( T 0 = 22 431.978(7) and 22 090.08(7) cm (-1)) based on previously reported mass-selective resonance-enhanced ionization spectra and the rotational structure. A spectral fit in MgC 4H yields the rotational constants B'' = 0.04619(19) cm (-1) for the X (2)Sigma (+) state and B' = 0.04748(20) cm (-1) for A (2)Pi. Astrophysical implications are briefly addressed.
authors: Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056, Basel, Switzerland.
authors: Egor
authors: E
authors: Chasovskikh
authors: Evan B
authors: EB
authors: Jochnowitz
authors: John P
authors: JP
authors: Maier