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脉冲激光激发NaK 21Σ＋←11Σ＋跃迁，单模Ti宝石激光器激发21Σ＋至高位态61Σ＋，研究了61Σ＋与H2碰撞中的碰撞转移。3 D→4 P（1.7μm ）和5 S→4 P（1.24μm ）荧光发射说明了预解离和碰撞解离的产生。在不同的H2密度下，通过以上能级的荧光测量得到了预解离率，碰撞解离及碰撞转移速率系数ΓP3D ＝（5.3±2.5）×108 s-1，ΓP5S ＝（3.1±1.5）×108 s-1，k3D ＝（3.7±1.7）×10-11 cm3· s-1，k5S ＝（2.9±1.4）×10-11 cm3· s-1，k4P→4S＝（1.1±0.5）×10-11 cm3· s-1，k3D→4P＝（6.5±3.1）×10-12 cm3· s-1，k5S→4P＝（4.1±1.9）×10-12 cm3· s-1。在不同 H2密度下，记录时间分辨荧光，由Stern-Volmer公式得到61Σ＋→21Σ＋，21Σ＋→11Σ＋的自发辐射寿命分别为（28±10） ns和（15±4） ns。61Σ＋→21Σ＋，61Σ＋→11Σ＋及21Σ＋→11Σ＋分子态间与H2的碰撞转移速率系数分别为（1.8±0.6）×10-11 cm3· s-1，（1.6±0.5）×10-10 cm3· s-1和（6.3±1.9）×10-11 cm3· s-1。转移到H2的振动、转动和平动能各占总转移能的0.58，0.03和0.39。主要能量转移至振动和平动能，支持61Σ＋- H2间的共线型碰撞机制。“,”The radiative lifetimes and rate coefficients for deactivation of high lying 61Σ+ state of NaK by collisions with H2 were studied .An OPO laser was set to a particular 21Σ+ ←11Σ+ transition .Another single mode Ti sapphire laser was then used to excite molecule from 21Σ+ level to the 61Σ+ state .The predissociation was monitored by the atomic potassium emission at the 3D→4P (1.7 μm) or the S→4P(1.24μm) ,while bound state radiative processes were monitored by total fluorescence from the upper state to the various levels ,all studied as a function of H2 density .The values for predissociation ,collisional dissociation and collisional depopulation rate coefficients were obtained .The decay signal of the time resolved fluorescence from the 61Σ+ →21Σ+ ,61Σ+ →11Σ+ or 21Σ+ →11Σ+ transition was monitored .Based on the Stern-Volmer equation ,the radiative lifetimes were monitored for 61Σ+ →21Σ+ and 21Σ+ →11Σ+ transition .The rate coefficients for deactivation of collisions with H 2 were moni-tored for 61Σ+ →21Σ+ ,61Σ+ →11Σ+ and 21Σ+ →11Σ+ .When the density of H2 was 1019 cm -3 ,the total collisional transfer en-ergy (15 426 cm-1 ) and radiative energy (10 215 cm -1 ) were obtained .The relative fraction ( , ,) of average en-ergy disposal was derived as (0.58 ,0.03 ,0.39); , , represent separately the relative fraction of average energy disposal among vibration ,rotation and translation .The major vibrational and translational energy release supports the assump-tion that the 61Σ+-H2 collision occurs primarily in a collisional energy transfer mechanism .In this experiment ,alkali molecules relative energy population ratio was determined through using the time integrated intensity ,so we can get the total transfer ener-gy .That the NaK (61Σ+ ) energy transfers to the H2 vibrational ,rotational and translational energy was quantitatively given for the first time ,which illustrates the collisional mechanism .