脉冲激光激发Rb原子至6D态， Rb(6D)与H2反应生成RbH(Х 1Σ+,ν″=0～2)振动态。 研究了RbH(Х 1Σ+)高位振动态与H2， N2间的碰撞弛豫过程， 利用泛频泵浦分别激发Х 1Σ+(ν″=0)至Х 1Σ+(ν″=15～22)各振动态,检测激光激发Х 1Σ+(ν″)至A 1Σ+(ν′)， 测量A 1Σ+(ν′)的时间分辨激光感应荧光光谱， 利用Stern-Volmer方程， 得到振动能级ν″的总的弛豫速率系数kν(H2)。 在H2和N2的混合气体中， 总弛豫速率系数kν(H2+N2)与α（H2的摩尔配比）成直线的关系,其斜率为kν(H2)－kν(N2)， 而截距为kν(N2)。 对于ν″<18主要发生单量子弛豫(Δν=1)过程， kν(H2)和kν(N2)与振动量子数ν″均成线性增加关系。 对于ν″≥18， 多量子弛豫(Δν≥2)过程及共振振动-振动转移起重要作用。 对于RbH(ν″=21)+N2(0)， 测量ν″=16的布居数时间演化轮廓， 在20 μs内有一个锐锋， 在100～200 μs内有一个较低的宽峰， 锐锋相应于RbH(ν″=21)+N2(0)→RbH(ν″=16)+N2(1)的共振转移过程， 而宽峰是由相继的单量子过程产生的。

Rb-H2 mixture was irradiated with pulses of 696.4 nm radiation from a OPO laser, populating 6D state by two-photon absorption. The vibrational levels of RbH(Х 1Σ+,ν″=0～2) generated in the reaction of Rb(6D) with H2. Vibrational-state-specific total-removal relaxation rate coefficients, kν(M), for RbH(Х 1Σ+,ν″=15～22) by M=H2 and N2 were investigated in a pump and probe configuration. By the overtone pumping with a cw diode laser, highly vibrational states ν″=15～22 of RbH in its ground electronic state were obtained. Another diode laser was used to probe the prepared vibrational state. The decay signal of laser induced time-resolved fluorescence from A 1Σ+(ν′)→Х 1Σ+(ν″) transition was monitored. Based on the Stern-Volmer equation, the total relaxation rate coefficient kν(H2) were yielded. A plot of kν(H2+N2) vs α(mole fraction H2) yields a line with a slope of kν(H2)-kν(N2) and an intercept of kν(N2). The values of kν(H2) obtained from the slope of the fitted lines compare well with determined values of the kν(H2) from the Sern-Volmer plots. At ν″<18, the rate coefficients kν(M) increases linearly with vibrational quantum number. This linear region is dominated by single quantum relaxation (Δν=1) collisional propensity rules. The region (ν″≥18) where the dependence is much stronger than linear shows significant contribution from multiquantum (Δν≥2) relaxation or resonant vibration-vibration energy transfer between highly vibrationally excited RbH and H2 or N2. For RbH(ν″)+N2(0), we measured the time-profile of ν″=16 after preparation of ν″=21. A clear bimodal distribution was observed. The first peak is due to resonant vibration-vibration energy transfer: RbH(ν″=21)+N2(0)→RbH(ν″=16)+N2(1). The much broader second peak, at longer time delays, is due to sequential single-quantum relaxation. Although the second process results in a distribution that is much more spread out in time, the peak height is in the same order of magnitude, indicating that the two processes are at least comparable in probability.