CF自由基二光子共振增强多光子电离研究:5p Rydberg态观测与分析

STUDY ON THE TWO PHOTON RESONACE ENHANCED MULTIPHOTON IONIZATION OF CF RADICALS: DETERMINATION AND ANALYSIS OF 5p RYDBERG STATE 

报道２６０—３６０ｎｍ波长范围内ＣＦ自由基（２＋１）共振增强多光子电离（ＲＥＭＰＩ）激发谱的研究．ＣＦ自由基通过Ａｒ／ＣＦ４，Ａｒ／ＣＦ２Ｃｌ２或Ａｒ／ＣＦ３ＣＯＯＨ混合气体的直流脉冲放电产生．在２６０—２９５ｎｍ波长范围内，观测到一个新的高Ｒｙｄｂｅｒｙ态振动序列，其带源位于２９５２２ｎｍ（２ｈν＝６７７４６ｃｍ－１），分析表明，该振动序列来源于５ｐＲｙｄｂｅｒｇ态的二光子共振激发，测得的振动频率和非谐性常数分别为１８４８和１８５ｃｍ－１，其量子亏损值为δ＝０６２５．在３１０—３６０ｎｍ区，观测的ＣＦ自由基（２＋１）ＲＥＭＰＩ激发谱对应于３ｐπＤ２Πｒ（ｖ′＝２—６，ｒ＝１／２，３／２）共振激发，获得了该Ｒｙｄｂｅｒｇ态相关的光谱常数．

Abstract In this paper,(2+1) resonance enhanced multiphoton ionization(REMPI) spectra of CF radical between 260 360nm have been investigated. CF radicals were produced by a pulsed dc discharge in the mixtures of Ar/CF 4,Ar/CF 2Cl 2 or Ar/CF 3COOH.A new vibrational progression of 5p Rydberg state with band origin of 67746cm -1 were observed between 260 305nm.The vibrational frequency ω′ =1848cm -1 ,inharmonic constant ω e χ e′ =18 5cm -1 and the quantum defect δ =0 625 have been determined by the assigned REMPI spectra. Furthermore,the (2+1)REMPI spectra of CF radical between 310 360nm,were also observed and assigned as 3p( v′= 2 6) resonant excitation. The related spectroscopic constants have been derived.