ULTRAFAST DYNAMICS OF LIGHT HARVESTING COMPLEXES

超快各向异性变化的测定可能具有很大的意义 在确定能量如何在不同的余因之间流动方面的价值 一个集合。各向异性测量技术已经被 显著改进，以使连贯和定向方面 可以高精度地确定能量传递的范围。飞秒 细菌二聚体亚基内的瞬时动力学 利用魔角和电子显微镜研究了捕光复合体。 偏振泵浦-探测光谱学。170厘米~(-1)和~20的振荡 在各向同性信号中观察到cm-1、50 cm-1和115 cm-1。 各向异性为500 cm-1。的斯托克斯移位和退相 二聚体激子水平发生在低于50ps的时间尺度上。这个 重组聚集体表现出超快的光谱演化和 两相各向异性衰减。总体而言，结果支持一种观点 黄体生成素-1复合体内的能量迁移 二聚体亚基的状态间的散射激发转移。

The determination of ultrafast anisotropy changes can be of great value in determining how energy flows between different cofactors in an assembly. The techniques of anisotropy measurement have been significantly refined in order that coherent and orientational aspects of energy transfer can be determined with high accuracy. Femtosecond transient dynamics within the dimeric subunit of a bacterial light-harvesting complex have been investigated using magic angle and polarized pump-probe spectroscopy. Oscillations of 170 cm-1 and ~ 20 cm-1, 50 cm-1 and 115 cm-1 are observed in the isotropic signal and ~ 500 cm-1 in the anisotropy. The Stokes shift and dephasing of the dimer exciton levels occurs on a sub-50 fs timescale. The re-assembled aggregate exhibits ultrafast spectral evolution and biphasic anisotropy decay. Collectively, the results support a view of energy migration within LH-1 complexes as proceeding by strongly scattered excitation transfer between states of the dimeric subunits.