Dalton Discussion 13: Inorganic photophysics and photochemistry: Fundamentals and applications (DD13)

Welcome to the special issue of Dalton Transactions associated with the ‘Dalton Discussion 13’ meeting ‘Inorganic Photophysics and Photochemistry: Fundamentals and Applications’ held in Sheffield, in September 10th–12th 2012. The meeting attracted over 100 national and international delegates, and included 24 talks (based on the contents of the 24 papers in this issue), over 50 posters, and a lot of lively discussion.

The interaction of light with matter is one of the most fundamentally important areas in the physical sciences. We can trace the subject back through history to the earliest appreciation of the aesthetic consequences of particular absorption spectra in dyes and pigments. Subsequent milestones include (amongst many!) discovery of the slow photochemical processes used in early photography; Einstein's statement of the quantized nature of light via the photoelectric effect; the development by Porter and Norrish of ‘flash photolysis’ which allowed transient species to be interrogated in time-resolved fashion; and the gradual evolution of this revolutionary method towards ‘femtochemistry’ and recently even faster timescales, where the advent of lasers and constant technological developments allow visualisation of transient processes on a timescale many orders of magnitude faster than was available to Porter and Norrish. Modern ultrafast optical and X-ray methods from many advanced laboratories world-wide were an integrated part of the Discussion, including amongst others the Swiss Light Source, Diamond Light Source and the Lasers for Science Facility (UK), University of Ohio (USA), or The Photon Factory (New Zealand). Applications of photochemistry and photophysics are now developing at a huge rate. The subject spans the range of disciplines from the immediately practical (such as dye-sensitized solar cells, photocatalysis, two-photon imaging and photodynamic therapy for medical applications amongst others) to those that are still emerging such as light-induced control of chemical reactivity, light-driven molecular electronic devices, or nuclear waste processing.

To try and encompass as much of this broad field as possible in twenty-four papers in a two-day meeting was an interesting challenge. The themes of the four sessions (Solar energy; Energy and electron transfer; Applications of strongly emissive complexes; Bond breaking and isomerisation) aimed to include both fundamental new science as well as some of the most important new practical applications of photophysics and photochemistry, where advanced synthetic and physical methods are intrinsically integrated. The papers from the four ‘keynote’ speakers (and their associated ‘Perspective’ review articles) alone illustrate this diversity. Prof. Rich Eisenberg addressed the hugely important topic of solar energy harvesting and photochemical production of H₂ using metal complexes, with an emphasis on developing systems based on earth-abundant metals. Prof. Majed Chergui gave a fascinating talk on cutting-edge physical methods that allow femtosecond-timescale X-ray and multidimensional optical studies which tell us what happens in molecules and ions at the very earliest stages after absorption of light. Prof. Luisa De Cola showed how some simple but strongly luminescent metal complexes can be used as the basis of a wide range of self-assembled gels and materials with remarkable photophysical properties; and finally Prof. Peter Ford highlighted possible medicinal applications of metal complexes in which energy-transfer from quantum dot antenna groups could result in the controlled release of pharmacologically important small molecules such as NO at targeted sites in the body. Other papers by invited speakers include polyoxometallate-based water oxidation catalysis (Prof. Craig Hill), biological sensing using chiral Eu(III) complexes (Prof. David Parker), new sensitisers for dye-sensitised solar cells (Prof. Leif Hammarström) and recent advances in computational chemistry illustrated by studies on light-induced isomerisation in Re(I) complexes (Prof. Chantal Daniel).

We hope you will find this special issue of Dalton Transactions as interesting and valuable as the conference was. Special thanks are due to the scientific organising committee of DD13 (in no particular order: Profs. Robin Perutz, Tony Vlcek, Mike George, Steve Faulkner, Andy Beeby, Tony Harriman, and Drs. Zoe Pikramenou and Neil Robertson), and to the RSC staff (Kirsty Gould, Charlotte Beard and Fiona McKenzie) for the excellent organisation and running of the meeting. But most of all, we wish to thank all the participants for making the meeting a truly exciting and forward-looking event. We hope that you will find this special issue interesting and inspiring.

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