Ultrafast excitation of out-of-plane vibrations and vibrational energy redistribution after internal conversion of 4-nitroaniline
Ultrafast excitation of out-of-plane vibrations and vibrational energy redistribution after internal conversion of 4-nitroaniline
复制标题
4-硝基苯胺内转换后面外振动的超快激发和振动能量重新分布
DOI：
10.1063/1.1530583
复制
发表时间：
2003
影响因子：
4.4
通讯作者：
J. Dreyer
中科院分区：
文献类型：
--
作者：
V. Kozich;W. Werncke;A. I. Vodchits;J. Dreyer
利用皮秒反斯托克斯共振拉曼光谱研究了对硝基苯胺（PNA）及其同位素标记物内转换后电子基态的超快振动激发和能量再分配.在PNA、PNA-di-15 N和PNA-D4中，泛频的反斯托克斯拉曼线和/或面外振动的组合带显示出接近约0.5 ps的电子激发态的衰减时间的上升时间和明显的过量布居。与这样的快速动力学相比，强拉曼活性全对称模式显示出相当慢的皮秒上升时间。我们的研究结果表明，主激发的面外振动的内部转换和二次激发的强烈拉曼主动振动的振动能量的重新分配。
Ultrafast vibrational excitation and energy redistribution in the electronic ground state after internal conversion of 4-nitroaniline (PNA) and isotope labeled analogs is investigated by picosecond anti-Stokes resonance Raman spectroscopy. In PNA, PNA-di-15N and PNA-D4, anti-Stokes Raman lines of overtones and/or combination bands of out-of-plane vibrations display risetimes close to the decay time of the electronically excited state of about 0.5 ps and pronounced excess populations. Compared to such fast dynamics, the strongly Raman active totally-symmetric modes show a considerably slower picosecond rise time. Our results indicate primary excitation of out-of-plane vibrations by internal conversion and secondary excitation of strongly Raman active vibrations by redistribution of the vibrational energy.