Spectroscopic investigation of the A ~1A'-X~1A' electronic transitionof HSiNCO

摘要

The first spectroscopic observation of the previously unknown species HSiNCO has been reported.HSiNCO was generated by the fragmentation of trimethylsilylisocyanate with a high-voltagedischarge source. The 0_0~0 band of the A ~1A"-X~1A ' transition has been recorded with full rotationalresolution using laser-induced fluorescence spectroscopy and ground and excited state rotational andcentrifugal distortion constants determined. Ten additional vibrational bands belonging to HSiNCOhave also been observed in the laser-induced fluorescence spectrum and have been assigned basedon predicted anharmonic vibrational frequencies. Due to the large change in geometry uponexcitation, a number of axis-rotation peaks have been observed in the 0_0~0 band and the axis-rotationangle (θ_T) has been estimated to be 0.6 ° ± 0.2°. Dispersed fluorescence spectroscopy has beencarried out and v8 (the N–C-O out-of-plane bending mode) and a number of overtones of v4 (theSi–H wagging mode) have been observed in the ground electronic state.