Parkinson Dilworth Y, Lee Hohjai, Fleming Graham R
Department of Chemistry, University of California, Berkeley, California 94720, USA.
J Phys Chem B. 2007 Jun 28;111(25):7449-56. doi: 10.1021/jp070029q. Epub 2007 May 26.
One- and two-color, three-pulse photon echo peak shift spectroscopy (1C and 2C3PEPS) was used to estimate the electronic coupling between the accessory bacteriochlorophyll (B) and the bacteriopheophytin (H) in the reaction center of the purple photosynthetic bacterium Rhodobacter sphaeroides as approximately 170 +/- 30 cm-1. This is the first direct experimental determination of this parameter; it is within the range of values found in previously published calculations. The 1C3PEPS signal of the Qy band of the bacteriochlorophyll B shows that it is weakly coupled to nuclear motions of the bath, whereas the 1C3PEPS signal of the Qy band of the bacteriopheophytin, H, shows that it is more strongly coupled to the bath, but has minimal inhomogeneous broadening. Our simulations capture the major features of the data with the theoretical framework developed in our group to separately calculate the response functions and population dynamics.
采用单色和双色三脉冲光子回波峰移光谱法（1C和2C3PEPS）估算了紫色光合细菌球形红杆菌反应中心中辅助细菌叶绿素（B）与细菌脱镁叶绿素（H）之间的电子耦合，约为170±30 cm-1。这是该参数的首次直接实验测定；它在先前发表的计算值范围内。细菌叶绿素B的Qy带的1C3PEPS信号表明它与溶剂的核运动弱耦合，而细菌脱镁叶绿素H的Qy带的1C3PEPS信号表明它与溶剂的耦合更强，但非均匀展宽最小。我们的模拟利用我们团队开发的理论框架捕捉了数据的主要特征，以分别计算响应函数和布居动力学。
