title: Vibrationally hot bands of the SiCN Ã 2Δ - X̃ 2Π system.
abstract: We have generated SiCN in supersonic free jet expansions and observed the laser induced fluorescence (LIF) spectrum. In addition to the vibronic bands from the vibrationless level of the X̃ (2)Π state, the hot bands from the bending vibrational level, Ã (01(1)0) (2)Φ - X̃ (01(1)0) (2)Δ and Ã (01(1)0) (2)Π - X̃ (01(1)0) (2)Σ((-)), have been measured. The rotational energy levels were reasonably analyzed as those of the (2)K' - (2)K″ transitions, but their line intensities calculated from the Hönl-London factors derived in the intermediate case between Hund's case (a) and (b) could not reproduce the observed spectra. The Hönl-London factors derived in the (2)Λ' - (2)Λ″ ((2)Δ - (2)Π) transition reasonably reproduced the spectra. It indicates that coupling between the electronic orbital and vibrational angular momenta is weak in the SiCN (2)Δ - (2)Π system, and a basis set of |Λ v2 l Σ;J P MJ>, the so-called "l-basis", better describes the system than that of |Λ v2 K Σ;J P MJ>.
authors: Faculty of Information Sciences, Hiroshima City University , Hiroshima 731-3194, Japan.
authors: Masaru
authors: M
authors: Fukushima
authors: Takashi
authors: T
authors: Ishiwata