Altmann J A, Beddard G S, Porter G
Ciba Found Symp. 1978(61):191-200. doi: 10.1002/9780470720431.ch10.
A simple model of the photosynthetic unit has been constructed and used for simulated Förster-type energy migration, fluorescence and intersystem crossing, in order to gain insight into the conditions that influence both the form and the lifetime of the fluorescence decay in vivo. The model consists of a two-dimensional random lattice with one central trap. The simulation was done by means of repetitive Monte Carlo-type computations. The results obtained show that the form of the decay curve changes from exponential to non-exponential, as the chlorophyll concentration (molecules/nm2) is increased. The fluorescence lifetimes (tau 1/e) were also found to decrease substantially with only slight increases inc concentration. At a concentration comparable to that of chlorophyll in the chloroplast, both the form of the fluorescence decay and the lifetime are in fair agreement with experiment in vivo. The reasons for non-exponentially of the decay as well as the properties of energy migration are discussed. Preliminary work involving the dependence of trapping rate on donor concentration is also presented.
构建了一个简单的光合单位模型，并将其用于模拟福斯特型能量迁移、荧光和系间窜越，以便深入了解影响体内荧光衰减形式和寿命的条件。该模型由一个带有一个中心陷阱的二维随机晶格组成。模拟通过重复的蒙特卡罗型计算进行。所得结果表明，随着叶绿素浓度（分子数/纳米²）的增加，衰减曲线的形式从指数型变为非指数型。还发现荧光寿命（τ₁/ₑ）随着浓度仅略有增加而大幅下降。在与叶绿体中叶绿素浓度相当的浓度下，荧光衰减的形式和寿命与体内实验相当吻合。讨论了衰减非指数性的原因以及能量迁移的特性。还介绍了涉及俘获速率对供体浓度依赖性的初步工作。
