Simulation of the photodeactivation of formamide in the nO-π* and π-π* states:: An ab initio on-the-fly surface-hopping dynamics study
Simulation of the photodeactivation of formamide in the nO-π* and π-π* states:: An ab initio on-the-fly surface-hopping dynamics study
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DOI：
10.1063/1.2804862
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发表时间：
2007-12-21
影响因子：
4.4
通讯作者：
Lischka, Hans
中科院分区：
文献类型：
--
作者：
Antol, Ivana;Eckert-Maksic, Mirjana;Lischka, Hans
采用基于多构型从头计算的直接轨道表面跳跃方法，研究了甲酰胺低激发态n（O）-pi（*）和pi-pi（*）的短时间光动力学（1 ps）.模拟结果表明，在这两种状态下，主要的失活过程是C-N键的解离。在基态，能量被转移到（a）HCO和NH 2碎片的平移运动，（B）从振动热的HCO碎片的额外C-H解离，或（c）NH3和CO的形成。除了C-N解离途径之外，发现C-O键裂变是pi-pi（*）动力学中的额外主要失活途径。从轨道的分数占用，甲酰胺的寿命估计：τ（S-1）=441 fs和τ（S-2）=66 fs。
The short-time photodynamics (1 ps) of formamide in its low-lying singlet excited n(O)-pi(*) and pi-pi(*) states have been investigated by the direct trajectory surface-hopping method based on multiconfigurational ab initio calculations. The simulations showed that in both states, the primary deactivation process is C-N bond dissociation. In the ground state, the energy is transferred to (a) translational motion of the HCO and NH2 fragments, (b) additional C-H dissociation from the vibrationally hot HCO fragment, or (c) formation of NH3 and CO. In addition to the C-N dissociation pathway, C-O bond fission is found to be an additional primary deactivation path in the pi-pi(*) dynamics. From fractional occupations of trajectories, lifetimes of formamide were estimated: tau(S-1)=441 fs and tau(S-2)=66 fs.