Phenomenological and Microscopic Theories of Structure
The NEC Corporation are to be congratulated for their foresight in setting up these biennial symposia on “The Fundamental Approach to New Material Phases”. This is indeed a timely step, for during the past few years a meaningful dialogue has started between fundamental theorists, materials scientists, and engineers who are interested in designing materials (see, for example [l]). This dialogue has arisen partly because quantum theorists are now beginning to predict from first principles the cohesion and relative structural stability of equilibrium and metastable phases. The advent of fast computers and the development of efficient computer codes have demonstrated that the intuitive and very simple Hartree-type equations of the Local Density Functional (LDF) approximation  are usually sufficient  to calculate the ground state properties of molecules and solids within a few percent (see, for example, , , and ). The present symposium has numerous papers which assess the accuracy of the LDF approximation in predicting the properties of microclusters.
KeywordsStructural Separation Band Filling Repulsive Energy Atomic Size Difference Biennial Symposium
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