DISSIPATIVE THREE-STATE SYSTEM AND THE PRIMARY ELECTRON TRANSFER IN THE BACTERIAL PHOTOSYNTHETIC REACTION CENTER
DISSIPATIVE THREE-STATE SYSTEM AND THE PRIMARY ELECTRON TRANSFER IN THE BACTERIAL PHOTOSYNTHETIC REACTION CENTER
复制标题
耗散三态系统与细菌光合反应中心的初级电子传递
DOI：
10.1021/j100090a027
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
C. Mak
中科院分区：
文献类型：
--
作者：
R. Egger;C. Mak
用一般耗散三态紧束缚模型研究了细菌光合作用中初级电荷分离的超快机制。利用实时路径积分，用精确的量子MonteCarlo方法计算了BChl[sub 2]*BChlBPh，BChl[sub 2][sup +]BChl[sup [minus]]BPh，BChl[sub 2][sup +]BChlBPh[sup [minus]]的瞬态布居.模拟结果表明，在至少两个参数区域内，耗散三态系统可以再现反应中心初始电荷分离的许多特征。在这两个地区，辅助细菌叶绿素人口保持小的整个电子转移和转移速率表现出实验观察到的逆温度依赖性。第一个区域与低的BChl[sub 2][sup +]BChl[sup [minus]]态和弱电子耦合相关联。在这个区域中，瞬态人口主要是单指数，和动态是一致的逐步（不相干）机制与非绝热电子转移速率。另一个区域与位于光激发特殊对（BChl[sub 2]*）上方的BChl [sub 2][sup +]BChl[sup [minus]]态相关联。参考文献52篇，图15，9个标签。
The mechanism of the ultrafast primary charge separation process in bacterial photosynthesis has been examined with a general dissipative three-state tight-binding model. Using real-time path integrals, the transient populations of the three electronic states (BChl[sub 2]*BChlBPh, BChl[sub 2][sup +]BChl[sup [minus]]BPh, BChl[sub 2][sup +]BChlBPh[sup [minus]]) involved in the reaction have been computed by numerically exact quantum Monte Carlo techniques. The simulations show that the dissipative three-state system can reproduce many characteristic features of the initial charge separation in the reaction center for at least two parameter regions. In both regions, the accessory bacteriochlorophyll population remains small throughout the electron transfer and the transfer rate exhibits the experimentally observed inverse temperature dependence. The first region is associated with a low-lying BChl[sub 2][sup +]BChl[sup [minus]] state and weak electronic couplings. In this region, the transient populations are predominantly monoexponential, and the dynamics is consistent with a stepwise (incoherent) mechanism with nonadiabatic electron-transfer rates. The other region is associated with a BChl[sub 2][sup +]BChl[sup [minus]] state lying above the photoexcited special pair (BChl[sub 2]*). 52 refs., 15 figs., 9 tabs.