AUGER, ZERO-ENERGY PHOTOELECTRON, COINCIDENCE SPECTROSCOPY - CHEMICAL-SITE-SELECTIVE AUGER-ELECTRON SPECTROSCOPY

The Auger electron spectrum associated with decay of a core-hole on th e terminal nitrogen and that associated with the central nitrogen of n itrous oxide, N2O, are obtained individually through the use of a coin cidence technique. Specifically, each of the two Auger electron spectr a is obtained by detection of Auger electrons in coincidence with near zero energy (threshold) photoelectrons at the respective ionization t hresholds. These zero energy electrons serve to identify the core-ioni zation continuum associated with the different Auger electrons. The sa lient features of the experimental spectra are in good agreement with theoretical calculations. The low counting rate generally associated w ith coincidence experiments, especially in the gas phase, is not encou ntered because the low energy electrons are collected over a 4pi solid angle. Also, velocity discrimination is accomplished by a spatial fil ter rather than by time-of-flight to utilize the maximum duty cycle of the synchrotron source. These data are believed to be the first examp les of chemical-site-selective molecular Auger spectra.