Single-photon vacuum ultraviolet (VUV) and two-color laser photoionization and pulsed field ionization-photoelectron (PFI-PE) measurements have been applied to the studies of transient radicals and metal-containing molecules generated by various in situ production schemes. Phenoxyl radical (C6H5O) has been prepared by flash pyrolysis of allyl phenyl ether in a hyperthermal pyrolysis nozzle of the Chen design. A Smalley-type ablation source has been installed and developed for the production of diatomic iron carbide (FeC) for two-color laser excitation-photoionization experiment. Sulfur monoxide radical (SO) has been prepared by using a supersonically cooled radical beam source based on the 193 nm excimer laser photodissociation of SO2. Based on the simulation of the rotational structures resolved in the PFI-PE bands of these species, highly accurate ionization energies (IEs) and spectroscopic constants are determined. These values are compared to IEs predicted by high-level ab initio quantum chemical calculations using the wave function based CCSDTQ(Full)/CBS approach (and its variations), which involves the approximation to the complete basis set (CBS) limit at the coupled cluster level up to full quadruple excitations. By benchmarking theoretical predictions with experimental results, a wide applicability of the CCSDTQ(Full)/CBS procedure in quantum chemical calculations of molecular energetic and spectroscopic properties have been demonstrated.

Owing to the advances of vacuum ultraviolet and ultrafast lasers and third generation synchrotron sources, the research on photoionization, photoelectrons, and photodetachment has gained much vitality in recent years. These new light sources, together with ingenious experimental techniques, such as the coincidence imaging, molecular beam, pulsed field ionization photoelectron, mass-analyzed threshold ion, and pulsed field ion pair schemes, have allowed spectroscopic, dynamic, and energetic studies of gaseous species to a new level of detail and accuracy. Profitable applications of these methods to liquids are emerging.This invaluable two-volume review consists of twenty-two chapters, focusing on recent developments in photoionization and photodetachment studies of atoms; molecules, transient species, clusters, and liquids.

Photoabsorption, Photoionization, and Photoelectron Spectroscopy explores photoabsorption processes involving individual, isolated molecules in the wavelength or photon energy range from the ionization thresholds of molecules (usually in the vacuum ultraviolet region) through the soft and hard X-ray region and beyond the ""K edge."" The interaction between electromagnetic radiation and isolated molecules based on photoabsorption, photoionization, and photoelectron spectroscopy studies is described, along with the techniques for measurement of total and partial cross sections. This book is comprised of eight chapters and examines the decomposition of molecules and molecular ions as well as mildly excited (valence shell excitation) and highly excited (inner shell excitation) molecules. After providing a general theoretical background, it discusses certain classes of atoms and molecules and considers electromagnetic interactions with gases. The following chapters focus on photoabsorption below the first ionization limit; quasi-discrete states above the first ionization potential; and the ionization continuum. Total photoabsorption and photoionization cross sections for selected molecules are also considered, and the angular distribution of photoelectrons is analyzed. The various measurement techniques are described in the last chapter. This monograph will be of interest to radiation chemists, radiation physicists, photochemists, mass spectrometrists, and perhaps radiation biologists.

Photoionization efficiency (PIE) and pulsed field ionization-photoelectron (PFI-PE) measurements of transition-metal-containing molecules have been conducted. The cold gaseous transition-metal-containing molecules were generated by a laser ablation supersonically cooled beam source. The CoC/CoC+, TiO/TiO+ and VN/VN+ systems were studied by using two-color UV-VIS resonance enhanced photoionization scheme. By exciting the molecules to single rotational levels of the intermediate state using a VIS dye laser prior to UV laser photoionization, we have obtained rotationally resolved PFI-PE spectra, allowing unambiguous rotational assignments and accurate determinations of energetic and spectroscopic constants. The TiO2/TiO2+ system was studied by using a VUV laser system. The recorded PIE and PFI-PE spectra also yields highly precise ionization energy and vibrational constants. We have also conducted theoretical calculations for these molecules by using state-of-the-art ab initio quantum calculations at the CCSDTQ/CBS level of theory. The energetic and spectroscopic results obtained in these studies have been compared with the theoretical results and are invaluable for benchmarking the theoretical calculation.

Electronic and photoelectron spectroscopy can provide extraordinarily detailed information on the properties of molecules and are in widespread use in the physical and chemical sciences. Applications extend beyond spectroscopy into important areas such as chemical dynamics, kinetics and atmospheric chemistry. This book aims to provide the reader with a firm grounding of the basic principles and experimental techniques employed. The extensive use of case studies effectively illustrates how spectra are assigned and how information can be extracted, communicating the matter in a compelling and instructive manner. Topics covered include laser-induced fluorescence, resonance-enhanced multiphoton ionization, cavity ringdown and ZEKE spectroscopy. The volume is for advanced undergraduate and graduate students taking courses in spectroscopy and will also be useful to anyone encountering electronic and/or photoelectron spectroscopy during their research.

The author, S. Hüfner, presents an authoritative and up-to-date introduction to the field by comprehensively treating the electronic structures of atoms, molecules, solids, and surfaces. Brief descriptions are given of inverse photoemission, spin-polarized photoemission and photoelectron diffraction. Experimental aspects are considered throughout the third edition book and the results are carefully interpreted in terms of the theory. A wealth of measured data is presented in tabulator form for easy use by experimentalists. The reader will learn about the basic technique of photoemission spectroscopy and obtain the necessary background for work based on this book.