This thesis focuses on theoretical analysis of the sophisticated ultrafast optical experiments that probe the crucial first few picoseconds of quantum light harvesting, making an important contribution to quantum biology, an exciting new field at the intersection of condensed matter, physical chemistry and biology. It provides new insights into the role of vibrational dynamics during singlet fission of organic pentacene thin films, and targeting the importance of vibrational dynamics in the design of nanoscale organic light harvesting devices, it also develops a new wavelet analysis technique to probe vibronic dynamics in time-resolved nonlinear optical experiments. Lastly, the thesis explores the theory of how non-linear “breather” vibrations are excited and propagate in the disordered nanostructures of photosynthetic proteins.

This book highlights the latest experimental and theoretical developments in the field of femtochemistry, with papers describing the physics and chemistry of ultrafast processes in small molecules, complex molecular systems, clusters, biological systems, solids, matrices, liquids and at surfaces and interfaces. The recent developments in frequency-domain studies of femtodynamics are also presented. In addition, the latest achievements in femtosecond control of chemical reactions are presented, together with the newest techniques in real-time probing of reactions such as ultrafast x-ray or electron diffraction. The papers are rich in references giving a clearcut state-of-the-art of the topics being discussed. The book should be a valuable tool to all persons in the field and to young scientists.Contributors include: A H Zewail, J Jortner, V S Letokhov, J Manz, R S Berry, C Wittig, K B Eisenthal, A W Castleman Jr., J T Hynes, W H Gadzuk, R Kosloff, S Mukamel, K R Wilson; G Fleming, D Wiersma, K Yoshihara, V Sundström, A Apkarian, N Scherer, A Myers, R Schinke, J R Huber, R B Gerber, G Gerber and P M Champion.

This book focuses on current applications of molecular quantum dynamics. Examples from all main subjects in the field, presented by the internationally renowned experts, illustrate the importance of the domain. Recent success in helping to understand experimental observations in fields like heterogeneous catalysis, photochemistry, reactive scattering, optical spectroscopy, or femto- and attosecond chemistry and spectroscopy underline that nuclear quantum mechanical effects affect many areas of chemical and physical research. In contrast to standard quantum chemistry calculations, where the nuclei are treated classically, molecular quantum dynamics can cover quantum mechanical effects in their motion. Many examples, ranging from fundamental to applied problems, are known today that are impacted by nuclear quantum mechanical effects, including phenomena like tunneling, zero point energy effects, or non-adiabatic transitions. Being important to correctly understand many observations in chemical, organic and biological systems, or for the understanding of molecular spectroscopy, the range of applications covered in this book comprises broad areas of science: from astrophysics and the physics and chemistry of the atmosphere, over elementary processes in chemistry, to biological processes (such as the first steps of photosynthesis or vision). Nevertheless, many researchers refrain from entering this domain. The book "Molecular Quantum Dynamics" offers them an accessible introduction. Although the calculation of large systems still presents a challenge - despite the considerable power of modern computers - new strategies have been developed to extend the studies to systems of increasing size. Such strategies are presented after a brief overview of the historical background. Strong emphasis is put on an educational presentation of the fundamental concepts, so that the reader can inform himself about the most important concepts, like eigenstates, wave packets, quantum mechanical resonances, entanglement, etc. The chosen examples highlight that high-level experiments and theory need to work closely together. This book thus is a must-read both for researchers working experimentally or theoretically in the concerned fields, and generally for anyone interested in the exciting world of molecular quantum dynamics.

This book contains important contributions from top international scientists on the-state-of-the-art of femtochemistry and femtobiology at the beginning of the new millennium. It consists of reviews and papers on ultrafast dynamics in molecular science.The coverage of topics highlights several important features of molecular science from the viewpoint of structure (space domain) and dynamics (time domain). First of all, the book presents the latest developments, such as experimental techniques for understanding ultrafast processes in gas, condensed and complex systems, including biological molecules, surfaces and nanostructures. At the same time it stresses the different ways to control the rates and pathways of reactive events in chemistry and biology. Particular emphasis is given to biological processes as an area where femtodynamics is becoming very useful for resolving the structural dynamics from techniques such as electron diffraction, and X-ray and IR spectroscopy. Finally, the latest developments in quantum control (in both theory and experiment) and the experimental pulse-shaping techniques are described.

The role of quantum coherence in promoting the e ciency of the initial stages of photosynthesis is an open and intriguing question. Lee, Cheng, and Fleming, Science 316, 1462 (2007) The understanding and design of functional biomaterials is one of today’s grand challenge areas that has sparked an intense exchange between biology, materials sciences, electronics, and various other disciplines. Many new - velopments are underway in organic photovoltaics, molecular electronics, and biomimetic research involving, e. g. , arti cal light-harvesting systems inspired by photosynthesis, along with a host of other concepts and device applications. In fact, materials scientists may well be advised to take advantage of Nature’s 3. 8 billion year head-start in designing new materials for light-harvesting and electro-optical applications. Since many of these developments reach into the molecular domain, the - derstanding of nano-structured functional materials equally necessitates f- damental aspects of molecular physics, chemistry, and biology. The elementary energy and charge transfer processes bear much similarity to the molecular phenomena that have been revealed in unprecedented detail by ultrafast op- cal spectroscopies. Indeed, these spectroscopies, which were initially developed and applied for the study of small molecular species, have already evolved into an invaluable tool to monitor ultrafast dynamics in complex biological and materials systems. The molecular-level phenomena in question are often of intrinsically quantum mechanical character, and involve tunneling, non-Born- Oppenheimer e ects, and quantum-mechanical phase coherence.

This landmark collective work introduces the physical, chemical, and biological principles underlying photosynthesis: light absorption, excitation energy transfer, and charge separation. It begins with an introduction to properties of various pigments, and the pigment proteins in plant, algae, and bacterial systems. It addresses the underlying physics of light harvesting and key spectroscopic methods, including data analysis. It discusses assembly of the natural system, its energy transfer properties, and regulatory mechanisms. It also addresses light-harvesting in artificial systems and the impact of photosynthesis on our environment. The chapter authors are amongst the field’s world recognized experts. Chapters are divided into five main parts, the first focused on pigments, their properties and biosynthesis, and the second section looking at photosynthetic proteins, including light harvesting in higher plants, algae, cyanobacteria, and green bacteria. The third part turns to energy transfer and electron transport, discussing modeling approaches, quantum aspects, photoinduced electron transfer, and redox potential modulation, followed by a section on experimental spectroscopy in light harvesting research. The concluding final section includes chapters on artificial photosynthesis, with topics such as use of cyanobacteria and algae for sustainable energy production. Robert Croce is Head of the Biophysics Group and full professor in biophysics of photosynthesis/energy at Vrije Universiteit, Amsterdam. Rienk van Grondelle is full professor at Vrije Universiteit, Amsterdam. Herbert van Amerongen is full professor of biophysics in the Department of Agrotechnology and Food Sciences at Wageningen University, where he is also director of the MicroSpectroscopy Research Facility. Ivo van Stokkum is associate professor in the Department of Physics and Astronomy, Faculty of Sciences, at Vrije Universiteit, Amsterdam.

Ultrafast Dynamics at the Nanoscale provides a combined experimental and theoretical insight into the molecular-level investigation of light-induced quantum processes in biological systems and nanostructured (bio)assemblies. Topics include DNA photostability and repair, photoactive proteins, biological and artificial light-harvesting systems, plasmonic nanostructures, and organic photovoltaic materials, whose common denominator is the key importance of ultrafast quantum effects at the border between the molecular scale and the nanoscale. The functionality and control of these systems have been under intense investigation in recent years in view of developing a detailed understanding of ultrafast nanoscale energy and charge transfer, as well as fostering novel technologies based on sustainable energy resources. Both experiment and theory have made big strides toward meeting the challenge of these truly complex systems. This book, thus, introduces the reader to cutting-edge developments in ultrafast nonlinear optical spectroscopies and the quantum dynamical simulation of the observed dynamics, including direct simulations of two-dimensional optical experiments. Taken together, these techniques attempt to elucidate whether the quantum coherent nature of ultrafast events enhances the efficiency of the relevant processes and where the quantum–classical boundary sets in, in these high-dimensional biological and material systems. The chapters contain well-illustrated accounts of the authors’ research work, including didactic introductory material, and address a multidisciplinary audience from chemistry, physics, biology, and materials sciences. The book is, therefore, a must-have for graduate- and postgraduate-level researchers who wish to learn about molecular nanoscience from a combined spectroscopic and theoretical viewpoint.