Zero kinetic energy photoelectron spectroscopy

See also Photoelectron Spectrometers Photoelectron Spectroscopy Zero Kinetic Energy Photoelectron Spectroscopy, Theory. 

ZEKE (zero kinetic energy) photoelectron spectroscopy has also been applied to negative ions [M]. In ZEKE work, the laser wavelengdi is swept tlirough photodetachment thresholds and only electrons with near-zero kinetic energy are... 

Muller-Dethlefs K and Schlag E W 1998 Chemical applications of zero kinetic energy (ZEKE) photoelectron spectroscopy Angew. Chem.-Int. Edit. 37 1346-74... 

Time-of-flight mass spectrometers have been used as detectors in a wider variety of experiments tlian any other mass spectrometer. This is especially true of spectroscopic applications, many of which are discussed in this encyclopedia. Unlike the other instruments described in this chapter, the TOP mass spectrometer is usually used for one purpose, to acquire the mass spectrum of a compound. They caimot generally be used for the kinds of ion-molecule chemistry discussed in this chapter, or structural characterization experiments such as collision-induced dissociation. Plowever, they are easily used as detectors for spectroscopic applications such as multi-photoionization (for the spectroscopy of molecular excited states) [38], zero kinetic energy electron spectroscopy [39] (ZEKE, for the precise measurement of ionization energies) and comcidence measurements (such as photoelectron-photoion coincidence spectroscopy [40] for the measurement of ion fragmentation breakdown diagrams). 

The factor limiting the resolution in ultraviolet photoelectron spectra is the inability to measure the kinetic energy of the photoelectrons with sufficient accuracy. The source of the problem points to a possible solution. If the photoelectrons could be produced with zero kinetic energy this cause of the loss of resolution would be largely removed. This is the basis of zero kinetic energy photoelectron (ZEKE-PE) spectroscopy. 

Recently, zero kinetic energy (ZEKE) photoelectron spectroscopy has been used to study the OH/NH tautomerism of 2-pyridone in the gas phase (95JPC8608). This work, which is expected to develop considerably, provides a wealth of information about that equilibrium for the states So, Sj, and Do (cation ground state). 

B. Zero Kinetic Energy Threshold Photoelectron Spectroscopy and... 

Photoelectron spectroscopy (PES, a non-mass spectral technique) [87] has proven to be very useful in providing information not only about ionization potentials, but also about the electronic and vibrational structure of atoms and molecules. Energy resolutions reported from PES are in the order of 10-15 meV. The resolution of PES still prevents the observation of rotational transitions, [79] and to overcome these limitations, PES has been further improved. In brief, the principle of zero kinetic energy photoelectron spectroscopy (ZEKE-PES or just ZEKE, also a nonmass spectral technique) [89-91] is based on distinguishing excited ions from ground state ions. 

Use of the supersonic jet in many branches of spectroscopy continues to increase. One technique which has made a considerable impact in recent years is that of zero kinetic energy photoelectron (ZEKE-PE) spectroscopy. Because of its increasing importance and the fact that it relates closely to ultraviolet photoelectron spectroscopy (UPS), which is described at length in earlier editions, I have included the new technique in Chapter 9. 

Autoionization-detected infrared spectroscopy (ADIR, which is a new technique)66 makes it possible to record infrared spectra of isolated bare molecular cations in molecular beams. Conventional time-of-flight mass spectroscopy (at zero kinetic energy) and photoelectron spectroscopy also enable the study of such cations. 

ZEKE-PEl zero kinetic energy pulsed field ionization photoelectron spectroscopy... 

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