Department of Chemistry, University of Sheffield, Sheffield S3 7HF, UK.
Department of Chemistry, University of Sheffield, Sheffield S3 7HF, UK. Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Science and Technology Facilities Council, Chilton, Oxfordshire OX11 0QX, UK.
Science. 2014 Dec 19;346(6216):1492-5. doi: 10.1126/science.1259995.
Electron transfer (ET) from donor to acceptor is often mediated by nuclear-electronic (vibronic) interactions in molecular bridges. Using an ultrafast electronic-vibrational-vibrational pulse-sequence, we demonstrate how the outcome of light-induced ET can be radically altered by mode-specific infrared (IR) excitation of vibrations that are coupled to the ET pathway. Picosecond narrow-band IR excitation of high-frequency bridge vibrations in an electronically excited covalent trans-acetylide platinum(II) donor-bridge-acceptor system in solution alters both the dynamics and the yields of competing ET pathways, completely switching a charge separation pathway off. These results offer a step toward quantum control of chemical reactivity by IR excitation.
电子从给体到受体的转移（ET）通常通过分子桥中的核-电子（振子）相互作用来介导。我们使用超快的电子-振动-振动脉冲序列，证明了通过特定于模式的红外（IR）激发与 ET 途径耦合的振动，如何彻底改变光诱导 ET 的结果。在溶液中处于电子激发态的共价反式乙炔基铂（II）给体-桥-受体系统中，皮秒窄带 IR 激发高频桥振动，改变了竞争 ET 途径的动力学和产率，完全关闭了电荷分离途径。这些结果为通过 IR 激发对化学反应性进行量子控制迈出了一步。
