【摘要】 用532.0nm激光激发Na2分子到B1∏u电子态,记录了Na原子的跃迁和Na2分子的A1∑_u~+-X1∑_g~+的谱带.由Na与Na2激发态发射的光谱及其强度可以认定在Na-Na2系统中的碰撞过程,Na原子线是Na2(B1∏u)到Na(3P)的碰擅能量转移产生的,顶解离过程也可产生原子线.而A1∑_u~+-X1∑_g~+谱带是由B1∏u到21∑_g~+的碰撞转移后再由21∑_g~+到A1∑_u~+的辐射而引起的.在360℃,根据辐射衰变率和荧光强度,得到Na2(B1∏u)到Na2(21∑_g~+)碰撞转移速率系数为7.1×10-10cm3s-1,而B1∏u的预解离率为2.3×106s-1.对不同振动能级间的碰撞激发转移[Na2(B1∏u)(v’=6)+Na(3S)→Na2(B1∏u)(v’=5,7)+Na(3S)]也进行了研究,并得到了v’=5和7时的速率系数分别是1.3×10-10cm3s-1和1.1×10-10cm3s-1.更多还原

【Abstract】 The B1∏u electronic state of Na2 is excited by the 532. 0nm laser line. The Na atomic transitions and the A1∑_u~+→X1∑_g~+ band of Na2 have been recorded. From the intensities and spectra of the Na and Na2 fluorescence, several collisional processes in the excited sodium atom-dimer system have been identified. The Na atomic lines are the result of collisional energy transferred from the Na2(B1∏u) to the Na(3P). Predisso-ciation process may also contribute to atomic fluorescence. The A1∑_u~+→X1∑_g~+band is interpreted through a populating mechanism involved collisional transfer from the B1∏u to the 21∑_g~+ followed by radiative transfer to the A1∑_u~+state. From the decay constants and fluorescence intensities,the rate coefficient at 360℃ for collisional energy transferred from Na2(B1∏u) to Na2(21∑_g~+) is 7.1×10-10cm3S-1. The predissociation rate of the B1∏u is 2. 3×106S-1. Collisional excitation transfer between different vibrational levels [i.e. ,Na2(B1∏u)(v’ = 6) + Na(3S)→Na2(B1∏u)(v’’ = 5,7)+Na(3S)] is also investiged. Rate coefficients for v’ being 5,7 are 1. 3×10-10cm3s-1and 1.1×10-10cm3s-1,respectively.更多还原