激光烧蚀Al热原子与CF4反应中C2的形成及其发光光谱研究

脉冲激光烧蚀金属平面铝靶产生的热原子与气相CF4碰撞反应中，在400—600nm之间观测到激发态C2分子的发光光谱，它们可归属为Swan带的d3Πg-a3Πu跃迁中Δv＝２，1，0，-1，-2五个振动序列（v'≤6）.光谱强度分析表明，C2激发态的振动温度达6340K左右.与激光烧蚀Al＋O2反应生成AlO的实验结果以及激光烧蚀Cu＋CF4的光谱比较，对比Al(2P1/2-2S1/2,3944nm）和C2的d—a跃迁（0—0）带带头（5165nm)的飞行时间轮廓，认为激发态的Al(2S1/2)原子通过 关键词： 激光烧蚀 发光光谱 C2分子

Formation and emission spectra of C2 swan band during the reaction of laser ablating target of aluminum with CF4 beam

The emission spectra of C2 Swan band transition has been observed in the 430nm-600nm region by Q switch laser ablating target of Al and reacting with CF4 beam.Five vibrational band sequences (Δv=2,1,0,-1 and -2) of d3Πg a3Πu are identified and the largest vibrational number of the excited state d is 6.Using a local thermal equilibrium model, the vibrational temperature of d state is about 6340K. Emission spectra from AlF have not been found. Comparing with the results of laser ablated Al+O2 system and similar experiment of Cu+CF4 system, while the time of flight profile of Al(2P1/2-2S1/2,3944nm)and(0,0)band head of C2 are analyzed, we consider that the primary reason of the producing of excited state d3Πg is the electronic energy transformation between excited states Al(2S1/2) and C2.