Near Infrared Spectrum Study On CN And SO~+

CN is a radical molecule of significance in astrophysics, which is widely present in atmosphere, comet, sun and interstellar space. In addition, CN acts as disturber that appears most of the discharge, for example, it is often observed when discharging H2O and CC14. Therefore, the spectroscopic study of CN is essential for further investigation of other transient species.SO+ cation is one of interstellar molecules. It plays important roles in both substance identification of industrial productions and fundamental searches. The lifetime of transient molecules decreases as the mass of molecule increases. Consequently, the producing rate of SO+ is rather less than that of O2+, and the detecting the spectra of SO+ is even more difficult.In the thesis, the Optical Heterodyne-Concentration Modulation Spectroscopy was used to record the spectra of CN that was produced by glow discharge. Based on the spectral line shape, phase of lines, spectral intensity distribution and combined difference relationship, about 220 lines of CN was assigned to 12 branches of the (3,1) band in theΑ2Πi-Χ2Σ+ system. The precise molecular parameters were obtained by nonlinear least-squares fitting the effective Hamiltonians. The line intensity is relevant with Boltzmann distribution, so the thermo-dynamical rotation temperature of CN could be derived through the relative intensity of lines within one branch. The obtained rotational temperature is close to the environmental temperature, demonstrating the spectroscopy is a good method for non-intrusive diagnosis of plasma.The b4Σ-a4Πi of SO+ was observed by Optical Heterodyne-Velocity Modulation Spectroscopy. The spectra were tentatively identified according to the spectral degrading to violet, line shape and spectral intensity relationship. The second order spin-orbit interaction responding to the energy levels splitting was used to explain the observed spectrum. Finally,240 lines were assigned to 12 branches of the (1,0) band in the b4Σ-a4Πi of SO+ The preliminary results are helpful for further study.