Wang Shu-Ying, Li Jia-Ling, Dai Kang, Shen Yi-Fan
Guang Pu Xue Yu Guang Pu Fen Xi. 2014 Nov;34(11):2887-91.
Energy transfer rate constants were measured for excited rovibrational levels of Na2 (X1Σ(g)+). Stimulated emission pumping was used to excited the levels v = 33-51, J = 11 via A-X transition. Laser induced fluorescence was used to follow the collision dynamics. Energy transfer processes induced by collisions with Ar and H2 were investigated. The decay curves for the parent level populations gave good fits to single exponential function. At v = 33-51, the total transfer rate constants increase linearly with vibrational quantum number. Parameterized expressions for the (48, 11)--to--(47, J) rate constants were fitted to the fractional populations of the satellite lines. This produced sets of relative rate constants. Absolute rate constants were then obtained by normalizing the sums of the relative rate constants to the total removal rate constants. For Na2 (v) + Ar, no multiquantum vibrational transfer was detected. For Na2 (v) + H2, a significant fraction of the initial population of highly vibrationally excited Na2 (X v = 48) relaxes to lower vibrational level (Δ v = -5). The time scale is much shorter than the known collisional lifetimes of the intervening vibrational levels and thus a sequential single-quantum relaxation mechanism can be explicitly ruled out. For v = 48, at least 40% of the initially prepared population, undergoes multiquantum vibrational relaxation. We discuss possible explanations of this result.
测量了Na2(X1Σ(g)+)激发振转能级的能量转移速率常数。利用受激发射泵浦通过A-X跃迁激发v = 33 - 51、J = 11的能级。用激光诱导荧光跟踪碰撞动力学。研究了与Ar和H2碰撞引发的能量转移过程。母能级布居的衰减曲线与单指数函数拟合良好。在v = 33 - 51时,总转移速率常数随振动量子数线性增加。将(48, 11)到(47, J)速率常数的参数化表达式拟合到卫星线的分数布居上。这产生了相对速率常数集。然后通过将相对速率常数之和归一化为总去除速率常数来获得绝对速率常数。对于Na2(v)+ Ar,未检测到多量子振动转移。对于Na2(v)+ H2,高度振动激发的Na2(X v = 48)初始布居的很大一部分弛豫到较低振动能级(Δv = -5)。时间尺度比中间振动能级已知的碰撞寿命短得多,因此可以明确排除顺序单量子弛豫机制。对于v = 48,至少40%的初始制备布居经历多量子振动弛豫。我们讨论了这一结果的可能解释。