Since the first edition of this book was published early in 1970, three major developments have occurred in the field of x-ray spectrochemical analysis. First, wavelength-dispersive spectrometry, in 1970 already securely established among instrumental analytical methods, has matured. Highly sophisticated, miniaturized, modular, solid-state circuitry has replaced elec tron-tube circuitry in the readout system. Computers are now widely used to program and control fully automated spectrometers and to store, process, and compute analytical concentrations directly and immediately from ac cumulated count data. Matrix effects have largely yielded to mathematical treatment. The problems associated with the ultralong-wavelength region have been largely surmounted. Indirect (association) methods have extended the applicability of x-ray spectrometry to the entire periodic table and even to certain classes of compounds. Modern commercial, computerized, auto matic, simultaneous x-ray spectrometers can index up to 60 specimens in turn into the measurement position and for each collect count data for up to 30 elements and read out the analytical results in 1--4 min-all corrected for absorption-enhancement and particle-size or surface-texture effects and wholly unattended. Sample preparation has long been the time-limiting step in x-ray spectrochemical analysis. Second, energy-dispersive spectrometry, in 1970 only beginning to assume its place among instrumental analytical methods, has undergone phenomenal development and application and, some believe, may supplant wavelength spectrometry for most applications in the foreseeable future.

On May 15-18, 1961, the 12th Annual Symposium on Spectros copy was held in Chicago. Over the twelve-year history of this meeting, it has continually grown and now ranks as one of the major technical meetings in the field of spectroscopy. The scope of the program itself represents a balance between research applications and control applications, between applied and the more fundamental aspects of spectroscopy. Papers are presented each year in the specialty areas of X -ray, ultraviolet, visible, infrared, Raman, EPR, and NMR spectroscopy. In many instances over the years, excellent work has been re ported at this symposium and no further publication was made. These reports were then essentially lost for further reference. It is the purpose of this publication to provide a source of reference for the papers presented at the 12th Annual Symposium. This first attempt at publishing a proceedings does not include the entire program. Several papers could not be given company clear ance for publication, and several more were intended for verbal presentation only and were never written for publication. I, as Coordinator of the Symposium, would like to express my gratitude to the Symposium Committee, John Ferraro, Elwin Davis, Joseph Ziomek, John Kapetan, L. S. Gray, Jr., Russell J. Hansen, J. A. Sheinkop, L. V. Azaroff, and Carl Moore, whose diligence and labor resulted in a truly fine symposium, and subsequently made pos sible this publication.