通过实验观测了微波硫灯的发光光谱.利用从头计算的多组态准简并微扰理论方法,采用cc-pVQZ基组计算了S2分子B^3Σu^--X^3Σg^-态和B″3Πu-X^3Σg^-态的跃迁矩及其振动态之间跃迁的弗兰克-康登因子,导出了S2分子振动分辨发射谱.同时,利用含时密度泛函方法计算了Sn(n=2~8)分子的吸收谱.将计算得到的S2分子振动分辨发射谱与实验所测得的光谱分布进行了比较分析,解释了微波硫灯的宽谱区发光光谱的特性.
The emission spectrum of microwave-driven sulfur lamp was obtained by experimental measurement. The emission moment of S2 B^3Σu^--X^3Σg^-andB″3Πu-X^3Σg^- electronic states and the Franck-Condon factors between their vibrational level were calculated by quantum ab initio method of multi-configuration quasi-degenerate perturbation theory and cc-pVQZ basic set, then, their emission spectra were derived. Absorption spectra of Sn ( n = 2-8 ) molecules were also calculated via time-dependent density functional theory. The emission spectrum and experimental one of S2 molecules were took step to compare and analyze. The results can be used to well explain the emission spectrum characteristic of the microwave-driven sulfur lamp. The theoretical simulation results can well guide the further experiments to fit better with sun's spectrum.