【摘要】 用一束波长为 2 10 .2 7nm的激光将CS2 分子激发至预离解态1B2 (1Σ+ u) ,用另一束激光通过激光诱导荧光 (LIF)方法检测碎片CS ,在 2 5 0 .5～ 2 86 .5nm获得了CS碎片A1Π←X1Σ+ 振转分辨的激发谱 .通过对光谱强度的分析 ,获得了CS碎片v″ =0～ 8的振动布居和v″=1,4～ 8振动态的转动布居 .结果发现 ,碎片CS的振动布居呈双模结构 ,分别对应于CS2 分子1B2 (1Σ+ u)态的两个解离通道 ,即CS(X1Σ+ ,v″=0～ 9) +S(3 PJ)和CS(X1Σ+ ,v″ =0～ 1)+S(1B2 ) .由此得到两个解离通道的分支比S(3 PJ) :S(1B2 )为 5 .6± 1.2 .与前人 193nm处的研究结果相比 ,2 10 .2 7nm激发更有利于S(3 PJ)通道的生成 .此外 ,实验还发现CS的转动布居不满足热平衡分布 ,为两个Boltzmann分布的合成更多还原

【Abstract】 The rotational and vibrational population of nascent CS(X 1Σ +) fragment, produced from dissociation of CS 2 1B 2( 1Σ + u) at 210.27 nm, were studied with laser-induced fluorescence (LIF) spectrum in the wavelength range of 250.5 to 286.5 nm. It was found that the vibrational population of CS(X 1Σ +) consists of two parts, corresponding to the contributions from two dissociation channels, CS(X 1Σ +)+S( 3P J) and CS(X 1Σ +)+S( 1B 2). The dissociation channel branching ratio, S( 3P J)/S( 1B 2), was determined to be 5.6±1.2 from the population. Additionally, the rotational population of some vibrational states (v″= 1, 4～8) of CS(X 1Σ +) were obtained from the rotationally resolved LIF spectrum, and were found to be non-Boltzmanian.更多还原