Setting the pace for progress and innovation . . . "There is no doubt that these are 'hot and exciting' research areas . . . [Advances in Photochemistry] could easily serve as a definitive source of background information for future researchers." --Journal of the American Chemical Society "For any library wishing to maintain a first-rate reference series on the photochemical literature. --Physics Today More than a simple survey of the current literature, Advances in Photochemistry offers critical evaluations written by internationally recognized experts. These pioneering scientists offer unique and varied points of view of the existing data. Their articles are challenging as well as provocative and are intended to stimulate discussion, promote further research, and encourage new developments in the field. In this volume Optical Single-Molecule Detection at Room Temperature ALFRED J. MEIXNER Pressure-Tuning Photochemistry of Metal Complexes in Solution RUDI VAN ELDIK AND PETER C. FORD Photo-Induced and Spontaneous Proton Tunneling in Molecular Solids H. PETER TROMMSDORFF The EPR-Spectroscopic D Parameter of Localized Triplet Diradicals as Probe for Electronic Effects in Benzyl-Type Monoradicals WALDEMAR ADAM, HEINRICH M. HARRER, FUMIO KITA, AND WERNER M. NAU Photothermal Studies of Photophysical and Photochemical Processes by the Transient Grating Method MASAHIDE TERAZIMA