The concept of energy densities and stress fields and its applications in quantum mechanical Coulomb systems within the Born-Oppenheimer approximation

Recent papers and ideas concerning the global stress tensor for crystals (obtained by a scaling of the total energy) as well as local stress and local energy (expressed by reduced density matrices or by Kohn-Sham orbitals) and related theorems and quantities like local momentum balances, forces, force sum rules, defect energies and defect stresses for perturbed crystals (surfaces, interfaces, point defects) are summarized. A new method for the calculation of relaxation or restoring forces is emphasized. (author)