That the field of Mossbauer spectroscopy continues for the remarks section of the index, and the inclusion to be an important growth area in science and tech of some new appendices and tables (such as the en nology, despite recent economic pressures, is ade ergy conversion tables, nuclear radius and moment quately evidenced by the present volume. Covering re data, and the report of the ASTM Task Group on search published only in the year 1969, its size is com Mossbauer Nomenclature and Conventions). The parable to its predecessor, Mossbauer Effect Data advertisement section, too, provides a collection of Index 1958-1965. With such continuing growth in information useful to many readers. many fields, the need for specialized information re In summary, the new editors are to be congratulated trieval tools for the research worker is now becoming for their excellent and tremendous effort in putting together such a fine compilation in a remarkably short an increasingly important internationally recognized time. The user community, I am sure, will strongly concern. MEDI 1969 satisfies much of this need for the community it addresses in a timely manner. urge them to continue this series, as I know their pred This work not only follows in the footsteps of its ecessor has been urged to help fill the gap for the years 1966-1968. predecessor, but also includes a number of important and very useful innovations. Among these are the classification of substances investigated according to ARTHUR H. MUIR, JR.

This year's issue is again exciting not only because People with common goals establish communities. Usually, in the natural sciences, communities originate it lists the 1 OOth excited resonance state, but also be around fields because institutions, conferences, and cause it contains extensive new information and addi 197 the literature are normally field oriented. In excep tional interesting articles on Au by Louis Roberts, 151 tional cases, communities have a method as the com Eu by Chris Barton and Norman Greenwood, and 129 mon bond, for instance, Mossbauer spectroscopy. The I by Hendrick deWaard. One innovation might be minimum requirement to be a "Mossbauer woman or suggested: for our irreproducible results we have the man" seems to be the possession of a Mossbauer sys International Journal of Irreproducible Results; how tem and the MEDI. Every member of the M6ssbauer ever, there is no literature for our reproducible nega community must have realized our extremely fortunate tive results. Sometimes nature's hidden tricks are un situation: before we put a drive system into motion known to us and experiments with some isotopes are we know within minutes if similar work has been pub tried unsuccessfully again and again. A chapter for lished somewhere in the world.

One of the most important - and unfortunately scientific information of interest in our field least advertised - applications of nuclear gamma from ali over the world in many languages, and resonance spectroscopy is the organized indexing documented, evaluated, and presented this in of scientific information. While there are only formation in a comprehensive format. two active workers in this field, the rest of us It tak.e this opportunity to congratulate the are the beneficiaries of their unique effort which Stevenses for their success, and to express my keeps us well informed in our own fields of in gratitude to them for their service to all of us. terest. This tenth volume of MEDI is a land 1 wish them very good luck. mark in an experiment in the distribution of scientific information, initiated by Art Muir R. L. M?SSBAUER and his group. Sin ce 1969, J ohn and Virginia Munich Stevens have explored new ways of gathering December, 1977 V Acknowledgments This year our operation was located at the Uni proofread the data and references, and in so versity of Nijmegen, The Netherlands, where we doing demonstrated a special kind of patience were working during a year lea ve of absence from and attention to detail. Other longtime assistants UNC-A. In Nijmegen Dr. Jan Trooster was our are Professor G. N. Belozerskii of USSR and Dr.

Mössbauer Effect: Principles and Applications focuses on the processes, methodologies, and reactions involved in Mössbauer effect, as well as atomic motion, use of the effect in studying hyperfine structures, quadropole coupling, and isomer shift. The manuscript first discusses resonant absorption, emission of gamma rays by nuclei, width of gamma-ray spectrum, and emission from bound atoms. The text then surveys counting, modulation, and low-temperature techniques. The publication offers information on relativity and the Mössbauer effect, atomic motion, quadropole coupling, and magnetic hyperfine structure. Discussions focus on gravitational red shift and combined magnetic and electric hyperfine coupling. The text then evaluates magnetism of metals and alloys, chemical applications, and linewidth and line shape. The manuscript is a valuable source of data for physicists and readers interested in the Mössbauer effect.

When presented with a new compound or material, the inorganic chemist will usually have several questions in mind about its composition and structure. Although a simple elemental analysis may answer many questions about its composition, the chemist will still have questions about its structure, and, ifthe material contains a metal atom, he will often want to know its oxidation state, coordination number and geometry. Further, at an increasingly frequent rate, the chemist may need details of the spin state, magnetic and perhaps dynamic properties of the material. If the investigator is fortunate, the material or compound may contain an ele ment such as iron, tin, antimony, iodine, gold, or one of several of the rare earth metals which are amenable to study by the Mossbauer effect. Often the Mossbauer effect can, sometimes with quite simple experiments, provide the answers to all of these questions. The goal of this book is to illustrate the effectiveness of the Mossbauer effect in providing the answers to the many questions that arise in char acterizing new materials and, indeed, in studying known materials in more detail. Several chapters introduce the effect to the novice and provide details about the various hyperfine interactions that are the "bread and butter" of the Mossbauer spectroscopist. Three chapters deal specifically with the experimental aspects of the technique and the increasing impor tance of sophisticated computer analysis of the resulting data.