【摘要】 通过微量CH3CN(36Pa)与He(660Pa)混合气体交流Penning辉光放电获得CN自由基分子,采用光外差磁旋转浓度调制光谱技术,在可见光波段16850～17480cm-1进行了转动分辨光谱测量,分别标识了CN分子红带A2Пi—X2Σ+(6,1)和(7,2)138条和118条的转动光谱(其余光谱为C2自由基及CN红带(8,3)带光谱)。理论拟合分子常数时考虑电子态间的微扰作用,采用有效哈密顿量矩阵对角化获得了A2Пi(ν=6,7)态更精确的分子常数及电子态A2Пi(ν=7)与X2Σ+(ν=11)之间的微扰常数ξ,η,总体拟合方差均小于实验误差0007cm-1,表明拟合结果是非常精确的。更多还原

【Abstract】 The CN radical was produced by Penning AC discharge of the mixture of trace acetonitrile （36 Pa） and helium （660 Pa） and the ro-vibrational spectra were measured by optical heterodyne magnetic rotation enhanced concentration modulation spectroscopy in the range of 16 850-17 480 cm^-1 . 138 lines and 118 lines were assigned to the （6, 1） and （7, 2） bands in red system A 2П_i—X 2Σ+ of CN respectively, while others were due to （8, 3） band in CN red system and C₂ Swan band system. More accurate molecular ^constants of A 2П_i（ν=6, 7） state and perturbation parameters ξ and η between A and X states were derived based on nonlinear ^least -^square fitting, individually, by diagonalizing the effective Hamiltonian matrix involving the perturbation elements of two ^electronical states and the standard deviation of fitting was less than the experimental uncertainty 0.007 cm^-1 , which implied the ^accuracy of our results.更多还原