CAJ | 학술논문

利用飞秒分辨的激光泵浦-探测技术结合飞行时间质谱和光电子速度成像方法研究了邻二氯苯第一电子单重激发态(S1)的超快动力学。邻二氯苯的S1态振动基态寿命为(651±10) ps,对应于S1振动基态向三重态的系间窜越过程。邻二氯苯S1的高振动激发9a218a2对应两个衰减通道,其中寿命为(458±12) fs的超快过程对应于由处于振动激发的S1向高振动激发的基态(S0)发生的内转换过程,而寿命为(90±10) ps过程则对应由S1态向三重态(T1)的系间窜越过程,电离产生的光电子能谱中长寿命的谱峰可能与系间窜越过程有关。 S1态高振动态的旋轨耦合程度比低振动态的更强,导致系间窜越过程更快。
이용비초분변적격광빙포-탐측기술결합비행시간질보화광전자속도성상방법연구료린이록분제일전자단중격발태(S1)적초쾌동역학。린이록분적S1태진동기태수명위(651±10) ps,대응우S1진동기태향삼중태적계간찬월과정。린이록분S1적고진동격발9a218a2대응량개쇠감통도,기중수명위(458±12) fs적초쾌과정대응우유처우진동격발적S1향고진동격발적기태(S0)발생적내전환과정,이수명위(90±10) ps과정칙대응유S1태향삼중태(T1)적계간찬월과정,전리산생적광전자능보중장수명적보봉가능여계간찬월과정유관。 S1태고진동태적선궤우합정도비저진동태적경강,도치계간찬월과정경쾌。
The dynamics of the first excited singlet electronic state (S1) ofo-dichlorobenzene was investigated in real time by the femtosecond pump-probe method combined with time-of-flight mass spectroscopy and the photoelectron velocity mapping technique. The lifetime of theS1 vibrational ground state was determined experimentaly to be (651 ± 10) ps, corresponding to the intersystem crossing process from theS1 state to the triplet state. Two decay channels were found in theS1 vibrationally excited mode 9a218a2. The fast process (lifetime constant (458 ± 12) fs) is because of the internal conversion from theS1 vibrationaly excited mode to the highly vibrationaly excited ground state (S0). The slow process (lifetime constant (90 ± 10) ps) is attributed to the intersystem crossing process from theS1 state to the triplet state (T1). Photoelectrons with long lifetime characteristics in the spectrum might be connected with the intersystem crossing process. Enhanced spin-orbital coupling in theS1 highly vibrationaly excited state accelerates the intersystem crossing process.