A practical method for modeling solids using semiempirical methods

Although many chemicals are solids, most quantum mechanical methods are lim ited to discrete systems and polymers. This is a direct result of the diffi culties associated with constructing a suitable Fock matrix For solids. By means of a simple approximation, the semiempirical NDDO methods have been e xtended to allow the Fock matrix for solids to be constructed. The resultin g methods can readily be applied to many different types of solids. Example s of the application of the method to solids of different crystal forms are presented. (C) 2000 Elsevier Science B.V. All rights reserved.