激发态H_2(X^1∑_g^+,v=1,J=1)之间的碰撞能量合并  

Energy Pooling collisions between Excited H_2(X^1∑_g^+,v=1,J=1)

作　　者：朱冬辉[1] 张彬[1] 沈异凡[1] 戴康[1] 

机构地区：[1]新疆大学物理科学与技术学院,乌鲁木齐830046

出　　处：《光散射学报》2011年第4期306-310,共5页The Journal of Light Scattering

基　　金：国家自然科学基金(10964011)

摘　　要：受激拉曼激发H2(0,1)基态的Q支得到H2(1,1)能级。在室温条件下,利用反斯托克斯拉曼散射(CARS)探测技术测量了碰撞能量合并(EP)过程H2(1,1)+H2(1,1)→H2(2,J)+H2(0,J″)及H2(1,1)与H2(1,J)转动能级间的碰撞转移速率系数。扫描CARS谱表明在H2(1,1)能级的碰撞能量转移过程中,仅使(2,1),(1,0)和(1,2)的振转能级得到布居。从H2(2,1)能级的时间分辨CARS强度的半对数描绘得到其退布率为(2.8±0.5)×105 s-1。用n1,n2,n3和n4,分别表示(1,1),(2,1),(1,0)和(1,2)能级上的布居数密度,对H2(1,1)能级的时间分辨CARS轮廓的形状进行理论模拟,并与实验结果进行比较,确定n1/n2=4.2。从扫描CARS谱的峰值得到n3/n2=1.2和n4/n2=1.0。确定被碰撞转移的H2有0.31处在v=2上,而在v=1上有0.69。碰撞能量合并的速率系数为(7.5±1.4)×10-14 cm3 s-1。对实验结果进行了讨论。Vibrational level of H2（v=1,J=1） was populated by stimulated Raman excitation of the Q branch line.The rate coefficients for the energy pooling（EP） collision H2（1,1）＋H2（1,1）→H2（2,J）＋H2（0,J″） and rotational energy transfer between H2（1,1） and H2（1,J） at room temperature have been measured using the Coherent Anti-Stokes Raman Scattering（CARS）technique.The scanned CARS spectra reveal that during energy transfer process H2 molecules are produced only at the（2,1）,（1,0） and（1,2） vibrational levels.The semilog plot of the time resolved CARS intensity for the H2（2,1） level yields collisional deactivation rate（2.8±0.5）×105 s-1.n1,n2,n3 and n4 represent the number densities of H2 at the levels（1,1）,（2,1）,（1,0） and（1,2） respectively.Through shape simulation of the time resolved CARS profiles of H2（1,1） under a kinetic model,the actual population n1/n2 is unambiguously determined to be of 4.2.From scanned CARS spectral peaks n3/n2=1.2 and n4/n2=1.0 are obtained.The H2 molecules produced by energy transfer process are 0.31 populated at the v=2 ande 0.69 at v=1.The rate coefficient for the energy pooling collision is estimated to be（7.5±1.4）×10-14 cm3 s-1.Relevance to another experiment is discussed.

关 键 词：能量转移 受激拉曼散射 CARS谱 速率系数 H2 

分 类 号：O562.5[理学—原子与分子物理]