Many-body properties calculated from the Kohn-Sham equations in density-functional theory

Most calculations of the electronic structure of solids within density-functional theory (or its extensions) rely on the Kohn-Sham equations. These equations describe an equivalent system of noninteracting particles. The solutions of these equations are used to construct the total energy and charge density of the system of interacting particles. In this paper we describe a procedure that is required for the calculation of arbitrary quantities pertaining to the interacting electrons from the Kohn-Sham equations describing a noninteracting reference frame.