从捕光天线到反应中心分子能量传递研究

利用飞秒时间分辨光谱技术研究了PSⅡ中捕光天线LHCⅡ内Chla分子和β-Car分子传递光能到反应中心的时间特性,实验测得Chla分子用了25 ps,β-Car分子用了250 ps.理论研究得出:25 ps是相邻Chl分子之间随机转移传能的时间常数,250 ps是LHCⅡ内相邻β-Car分子,通过Chla分子单步FÖrster共振传递、Dexter电子交换机制、激子转移把能量转移到反应中心的总时间.理论计算与实验结果基本符合,激子随机转移传递激发能快而有效.

Study on Molecule Energy Transfer from Light-harvesting Antenna to Reaction Center

Femtosecond time resolved spectrum techniques have been used to study the time characteristic of energy transfer from Chla and β-Car molecule of the LHCⅡ to the reaction center in the photosystem Ⅱ.By experiment Chla molecule uses 25 ps, β-Car molecules use 250 ps. Theory investigations has shown that 25 ps is a energy transfer time on random transfer between neighboring Chla molecules,250 ps is a energy transfer time on a one step FÖrster transfer, Dexter electron exchange, exciton transfer between neighboring β-Car and Chla molecules from the excited β-Car in the LHCⅡ to the reaction center. Theory counts are in agreement with the experiment results basically.