The Physics Underlying the Langreth-Mehl Scheme for Non-Uniform Systems

摘要: Simple physical arguments as well a solvable model Hamiltonian are used to understand the nature of approximate exchange-correlation functional developed by Langreth and Mehl for application extended systems atoms molecules. Although Langreth-Mehl cutoff procedure is crude, it argued on basis simple physics that basically correct. Despite rather widespread qualitative success this functional, in application, improvements necessary, methods making such explored.