MODERATELY-LARGE-EMBEDDED-CLUSTER APPROACH TO THE STUDY OF LOCAL DEFECTS IN SOLIDS - VACANCY AND SUBSTITUTIONAL IMPURITIES IN GRAPHITE

A method for studying local defects in solids is presented which is the development of an embedding approach first applied to the study of localized chemisorption. Its relationship with other embedding schemes is discussed, and it is shown that for its applicability larger cluster sizes are needed than customary in similar computations. This drawback is compensated by the characteristics of the embedding equations, which allow the method to be easily implemented starting from standard quantum-chemistry programs, and the self-consistent solution to be reached following well-tested procedures. A study of the isolated vacancy and of substitutional boron and nitrogen impurities in a monolayer of graphite is used to illustrate the method. © 1979 The American Physical Society.