Abstract We present a high-resolution spectroscopic study of the A ~ 1 B 2 - X ~ 1 A 1 transition of SiC 2 by laser-induced fluorescence. The gas-phase SiC 2 molecules are produced in a discharge plasma and cooled in a supersonic jet expansion. By employing a home-made single longitudinal mode optical parametric oscillator as the narrow bandwidth laser source, laser excitation spectra have been recorded with a transition frequency accuracy of ~ 0.004 cm - 1 for the 0 0 0 , 2 0 1 , 3 0 1 and 3 1 1 bands. Rotational analyses of the high-resolution data have yielded accurate spectroscopic constants, including the centrifugal distortion constants, for the upper vibronic states studied here.

中文翻译：

---

SiC2 A∼1B2-X∼1A1跃迁000、201、301和311波段的高分辨率光谱

摘要 我们通过激光诱导荧光对 SiC 2 的 A ~ 1 B 2 - X ~ 1 A 1 跃迁进行了高分辨率光谱研究。气相 SiC 2 分子在放电等离子体中产生并在超音速射流膨胀中冷却。通过采用自制的单纵模光学参量振荡器作为窄带宽激光源，记录的激光激发光谱的跃迁频率精度为~0.004 cm - 1 0 0 0 、2 0 1 、3 0 1 和3 1 1 波段。高分辨率数据的旋转分析产生了准确的光谱常数，包括离心畸变常数，用于此处研究的上振动状态。