The symposium consisted of four half-day sessions on topics at the forefront of semiconductor electrochemistry and solution-based processing including etching, patterning, passivation, porosity formation, electrochemical film growth, energy conversion materials, deposition, semiconductor surface functionalization, photoelectrochemical and optical properties, and other related processes. This issue of ECS Transactions contains 18 of the papers presented including invited papers by H. Föll (Christian-Albrechts University Kiel), J. N. Chazalviel (Ecole Polytechnique, CNRS), D. N. Buckley (University of Limerick, and Past President, ECS), J. D. Holmes (University College Cork), E. Chassaing (IRDEP, EDF-CNRS-ENSCP).

This issue of ECS Transactions includes papers based on presentations from the symposium "Processes at the Semiconductor Solution Interface 8," originally held at the 235th ECS Meeting in Dallas, Texas, May 26-30, 2019.

This ninth volume in the series concentrates on in situ spectroscopic methods and combines a balanced mixture of theory and applications, making it highly readable for chemists and physicists, as well as for materials scientists and engineers. As with the previous volumes, all the chapters continue the high standards of this series, containing numerous references to further reading and the original literature, for easy access to this new field. The editors have succeeded in selecting highly topical areas of research and in presenting authors who are leaders in their fields, covering such diverse topics as diffraction studies of the electrode-solution interface, thin organic films at electrode surfaces, linear and non-linear spectroscopy as well as sum frequency generation studies of the electrified solid-solution interface, plus quantitative SNIFTIRS and PM-IRRAS. Special attention is paid to recent advances and developments, which are critically and thoroughly discussed. The result is a compelling set of reviews, serving equally well as an excellent and up-to-date source of information for experienced researchers in the field, as well as as an introduction for newcomers.

Section 1 addresses the most recent developments in processes at the semiconductor-solution interface include etching, oxidation, passivation, film growth, porous semiconductor formation, electrochemical, photoelectrochemical, electroluminescence and photoluminescence processes, electroanalytical measurements and related topics on both elemental and compound semiconductors. Section 2 addresses the most recent developments in compound semiconductors encompassing advanced devices, materials growth, characterization, processing, device fabrication, reliability, and related topics.

The origin of this book lies in a time before one of the authors (J. O'M. B.) left the University of Pennsylvania bound for the Flinders University. His collaboration with Dennis Matthews at the University of Pennsylvania had contributed a singular experimental datum to the quantum theory of elec trode processes: the variation of the separation factor with potential, which could only be interpreted in terms of a quantum theory of electrode kinetics. The authors came together as a result of grad~ate work of one of them (S. U. M. K.) on the quantum mechanics and photo aspects of elec trode processes, and this book was written during a postdoctoral fellowship held by him at the Flinders University. Having stated the book's origin, it is worthwhile stating the rational izations the authors had for writing it. Historically, quantization in elec trochemistry began very early (1931) in the applications of the quantum theory to chemistry. (See the historical table on pages xviii-xix.) There was thereafter a cessation of work on the quantum theory in electrochemistry until a continuum dielectric viewpoint, based on Born's equation for solvation energy, began to be developed in the 1950s and snowballed during the 1960s.