Dissociative Recombination of Molecular Ions with Electrons is a comprehensive collection of refereed papers describing the latest developments in dissociative recombination research. The papers are written by the leading researchers in the field. The topics covered include the use of microwave afterglows, merged beams and storage rings to measure rate coefficients and to identify the products and their yields. The molecules studied range in size from the smallest, H2+, to bovine insulin ions. The theoretical papers cover the important role of Rydberg states and the use of wave packets and quantum defect theory to deduce cross sections, rate constants and quantum yields. Several theoretical and experimental papers address the controversial topic of H3+ dissociative recombination and its importance in the interstellar medium. Dissociative recombination studies of other molecular ions in the interstellar medium and in cometary and planetary atmospheres are covered. Ionization is an important competitive process to dissociative recombination and its competition with predissociation and its role in the reverse process of the association of neutral species is presented. Dissociative attachment, in which an electron attaches to a neutral molecule, has many similarities to dissociative recombination. The topics covered include the accurate calculation of electron affinities, attachment to molecules, clusters, and to species absorbed on solid surfaces and electron scattering by a molecular anion.

Dissociative recombination (DR) of molecular ions with electrons is a complex, poorly understood molecular process. Its critical role as a neutralising agent in the Earth's upper atmosphere is now well established and its occurrence in many natural and laboratory-produced plasma has been a strong motivation for studying the event. In this book theoretical concepts, experimental methodology and applications are united, revealing the governing principles behind the gas-phase reaction. The book takes the reader through the intellectual challenges posed, describing in detail dissociation mechanisms, dynamics, diatomic and polyatomic ions and related processes, including dissociative excitation, ion pair formation and photodissociation. With the final chapter dedicated to applications in astrophysics, atmospheric science, plasma physics and fusion research, this is a focused, definitive guide to a fundamental molecular process. The book will appeal to academics within physics, physical chemistry and related sciences.

Proceedings of a NATO ARW held in Saint Jacut de la Mer, Brittany, France, May 3-8, 1992

In this book, the latest developments in the study of the dissociative recombination of electrons and molecular ions are discussed. This process is of great importance in controlling the physical and chemical states of ionized gases. It has direct application to astrophysics, aeronomy, thermonuclear fusion research, plasma processing and combustion science.

Dissociative recombination is a complex molecular process that occurs in any plasma cold enough to contain molecular constituents. It is the dominant recombination process in planetary ionospheres and interstellar clouds. In this book, recent developments in the fields of molecular ion physics, atomic and molecular theory, astrochemistry, aeronomy and plasma physics are discussed.

Results of studies of the recombination of electrons with molecular positive ions are presented. Theoretical arguments indicate that the dissociative process -- in which a molecular ion captures an electron without change of energy, forming an unstable excited molecule which then dissociates -- provides a highly efficient recombination mechanism. The nature of the process responsible for the large recombination rates observed in Laboratory afterglow studies is investigated using combined microwave, optical spectrometric and interferometric, and mass spectrographic techniques. Dissociative recombination is shown to be the process operative in the laboratory studies, since it is found that (a) molecular positive ions must be present to observe a large recombination rate, (b) when diatomic ions are present, excited atoms are formed in the recombination process, and (c) these excited atoms have kinetic energy of dissociation substantially in excess of thermal energy. (Author).