碰撞诱导钠分子A1Σ+u→X1Σ+g的荧光光谱

用532.0 nm激光激发Na2分子到B1Πu电子态,记录了Na(3P)原子的跃迁和Na2分子的A1Σ+u-Χ1Σ+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(3P)原子线是Na2(B1Πu)到Na(3P)的碰撞能量转移产生的,预解离过程也可产生原子线.而A1Σ+u-Χ1Σ+g谱带是由B1Πu到21Σ+g的碰撞转移后再由21Σ+g到A1Σ+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(B1Πu)到Na2(21Σ+g)碰撞转移率系数为7.1×10-10 cm3s-1,而B1Πu的预解离率为2.3×106 s-1.

Collision-induced fluorescence of Na2:the A1Σ+u→Χ1Σ+g system

The B()~1Π_u electronic state of Na2 is excited by the 532.0?nm laser line.The Na(3P) atomic transitions and the A()~1Σ~+_u→X1Σ+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(3P) atomic lines are the result of collisional energy transfer from the Na_2 (B()~1Π_u) to the Na(3P).Predissociation process may also contribute to atomic fluorescence.The A1Σ+u→X1Σ+g band is interpreted through a populating mechanism involving collisional transfer from the B()~1Π_u to the 2()~1Σ~+_g followed by radiative transfer to the A1Σ+u state. From the decay constants and fluorescence intensities,the rate coefficient at 360℃ for collisional energy transfer from Na_2(B()~1Π_u) to Na_2(2()~1Σ~+_g) is 7.1×10~(-10)?cm~3S~(-1).The predissociation rate of the B()~1Π_u is 2.3×10~6?S~(-1).