SOME THOUGHTS ON THE SCOPE OF LINEAR SCALING SELF-CONSISTENT FIELD ELECTRONIC STRUCTURE METHODS

In this chapter a number of algorithms are described for the exact or approximate calculations of the Coulomb and Hartree-Fock exchange parts of the Fock matrix. Arguments in favor of efficient approximations without linear scaling behavior are presented if the goal of the investigation is to solve typical every day computational chemistry problems. Everyday computational chemistry problems are, in this context, understood as involving molecules with up to about 100 or 200 atoms. In particular, it is important to test new algorithms with respect to their efficiency in conjunction with basis sets and integral thresholds that are appropriate for actual application work. Some numerical examples for efficiency and accuracy of the methods that are discussed are provided.