Imperial College Laboratory for Ultrafast X-ray Diffraction (LUXD)

光诱导过程在自然界中是基本的。事实上，太阳是地球的能源，它的光在固有的超快时间尺度上，通过多种不同的分子过程被捕获和转换。虽然20世纪是科学时代，物质的结构在21世纪推动了许多科学发现和技术，但我们现在准备看到结构动力学作为科学和技术的驱动力出现。创造分子功能和光诱导过程的“分子电影”的愿望推动了超快结晶学领域的快速技术进步。一张图片胜过千言万语。事实上，对分子运动最直接的观测是原子坐标的“真实空间”中的时间分辨测量。空间分辨率是通过使用Angstrom波长辐射的结晶学获得的，而时间分辨率是通过为激发和X射线探头产生强烈的飞秒脉冲来实现的。激光技术的最新发展使得能够主要使用粉末衍射法建立能够进行飞秒时间分辨X射线结晶学的实验室仪器成为可能，该仪器将使广泛的科学应用成为可能，包括实验、光药学、太阳能电池研究、储能、光电子学、热释电、核相干研究、纳米光子学和等离子体学、胶体和生物分子结构。一个引人注目的例子将是一个基于染料的光开关分子的光异构化反应的演示，该分子用于光药学和能量存储。超快测量将确定有机分子顺反光异构化的激发态重构和非绝热动力学。这种影响通过在光药学靶标中的应用来证明，例如光调节生物分子靶分子中的底物结合。此外，研究太阳能材料照射后的结构动力学对于理解和优化功能至关重要，特别是随着太阳能电池技术的快速发展，新材料和效率的不断提高将需要对材料甚至工作器件进行超快的结构测量。

Light induced processes are fundamental in Nature. Indeed, the Sun is the earth's energy source and it's light is captured and converted in a multitude of different molecular processes, on intrinsic ultrafast time scale. Whilst the 20th century was the scientific era in which the structure of matter drove much scientific discovery and technology in the 21st century we are now poised to see the emergence of structural dynamics as a driving force in science and technology. The desire to create "molecular movies" of molecular function and light induced processes has driven rapid technological advances in the area of ultrafast crystallography. A picture says more than a thousand words. Indeed, the most direct observation of a molecular motion is a time resolved measurement in 'real-space' of the atomic coordinates. The spatial resolution is achieved by crystallography with Angstrom wavelength radiation, while the time resolution is achieved with the generation of intense femtosecond pulses for both the excitation and the X-ray probe. Recent developments in laser technology allow the construction of a laboratory based instrument that is capable of femtosecond time resolved X-ray crystallography primarily using the powder diffraction method.The instrumentation will enable a large range of science applications, including experiments photopharmacology, solar cell research, energy storage, optoelectronics, pyroelectrics, nuclear coherence research, nanophotonics and plasmonics, colloids and biomolecular structure. A compelling example will be the demonstration of a photoisomerisation reaction of a dye-based photoswitching molecule which is used for photopharmacology and energy storage. The ultrafast measurements will determine the excited state reconfiguration and non-adiabatic dynamics of cis/trans photoisomerisation of the organic molecule. The impact is demonstrated by usage of the indigoid moiety in photopharmacology targets such that light regulates the substrate binding in biomolecular target molecules.Additionally, studies of the structural dynamics following illumination of solar energy materials are vital to understand and optimise functions In particular, with the rapid developments in the solar cell technology, novel materials and continuous improvements in the efficiency will require ultrafast structural measurements of the materials and even working devices.