Investigating the ultrafast dynamics of natural and artificial light harvesting

植物、藻类和某些细菌能有效地捕捉地球上的大量阳光，以推动光合作用--光合作用是将二氧化碳和水转化为单糖的过程，用于植物生长。虽然已经建立了对自然光合作用的宏观理解，但支撑所谓光合作用“设计原则”的微观细节还没有完全详细。人们已经认识到包裹捕光叶绿素部分的蛋白质的几个作用，但导致其独特的沐浴反应的叶绿素和蛋白质残基之间的特定分子相互作用尚未得到实验研究。具有已知X射线晶体结构的模型蛋白质，只包含一个或两个可见的发色团，将被研究以揭示蛋白质作为结合残基和蛋白质口袋的函数的“浴”动力学。人为有效利用太阳通量的努力远没有那么有效，分子结构和总体功率转换效率之间的关系才开始出现在大量材料中，如有机块状异质结或半导体材料。在所有情况下，吸收的光都被用来诱导电荷分离成电子和空穴，但这种过程的机制和位置仍然是模糊的。超快多维光学光谱，如2D电子光谱，将被用来探索这些现象，以飞秒时间分辨率(1fs=百万亿分之一秒)创建组成分子之间的能量流图。

Plants, algae and certain bacteria efficiency capture the abundant sunlight incident on the Earth to drive photosynthesis- the process of converting carbon dioxide and water into simple sugars used for plant growth. Whilst a macroscopic understanding of natural photosynthesis has been established, microscopic details that underpin the so-called "design principles" of photosynthesis have yet to be fully detailed. Several roles for the protein that encapsulates the light harvesting chlorophyll moieties are recognised, but the specific molecular interactions between chlorophyll and protein residues that give rise to their unique bath response have eluded experimental studies. Model proteins with known x-ray crystal structures, that contain only one or two visible chromophores will be investigated to reveal the "bath" dynamics of the protein as a function of the binding residue and protein pocket.Man-made efforts to efficiency harness the solar flux have been far less effective, with relationships between the molecular structure and overall power conversion efficiencies only starting to emerge for a plethora of materials such as organic bulk-heterojunctions or semi-conducting materials. In all instances, the absorbed light is used to induce charge separation into electrons and holes, but the mechanism and location for such processes remain nebulous.Ultrafast multidimensional optical spectroscopies such as 2D electronic spectroscopy will be used to explore these phenomena, creating a map of energy flow between constituent molecules with femtosecond time resolution (1 fs = 1 millionth billionth of a second).