The Molecular Engineering of Oxides: 1989 MRS Fall Meeting Von Hippel Award Address
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his honor that I hâve chosen as the title of my talk, "The Molecular Engineering of Oxides." Back in the 1950s, I was part of the group at Lincoln Laboratory that developed the ferrite-core memory for the digital computer. This task involved an identification of the optimum ferrospinel composition and the development of a fabrication and testing process that would give a high yield of cores with acceptable physical properties. Its realization involved, as well, the development of a theoretical underetanding of the factors that détermine the shape
of a B-H hystérésis loop and of why an exquisite annealing procédure was required to develop controlled chemical inhomogeneities via the dynamic JahnTeller effect. This expérience made it clear to me that there was an urgent need to build bridges between the engineer and the materials scientist. The design engineer required new materials in order to enable invention to become economically compétitive in the marketplace. The materials scientist concerned with the identification of new practical materials or material configurations was continually in need of confrontation with engineering realities. Moreover, the design of a material having the particular properties specified by the engineer remained, at that time, more a matter of empiricism than of "molecular engineering." Today you are ail quite aware of this issue. In those days, I described the prob|em via the diagram of Figure 1; it distinguishes two legs that are critical for a healthy materials science effort. To the left is a "device" that has been invented by the design engineer, but it needs a material with spécifie properties for its commercial realization. Thèse properties are specified in terms of such "engineering parameters" as loss, breakdown voltage, or switching speed. Traditionally, the engineer has turned to a materials handbook to détermine whether any existing materials hâve properties that can be "engineered" to approximate his spécifications. Today, there is a symbiotic relationship developing between the engineer and the materials scientist that brings von Hip-
Professor John B. Goodenough The Materials Research Society presented its most prestigious award, the Von Hippel Award to Prof. John B. Goodenough during cérémonies held at the 1989 Fall Meeting in Boston, Massachusetts. Goodenough was cited for "distinguished contributions to the field of solid state sciences, where his insights, ideas, knowledge, and research hâve consistently drawn together the basic concepts of physics and chemistry in the conquest of wide-ranging fundamental topics." Prof. Goodenough has made pioneering contributions in many expérimental fields, including such diverse topics as development of ferrite-core random access memories, high pressure studies of perovskites, and the analysis of lithium ion conductivity in spinels. He has addressed the electronic structure of complex materials, with concepts fundamental to chemical bonding. In the days before band structure calculations were routine, Prof. Goodenough succeeded in
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