The Chadi total energy algorithm for determining surface geometries

摘要: The Chadi total energy minimization technique is probably the simplest, physically realistic approach for determining surface geometries of solids and has proved highly successful in predicting relaxation reconstruction a wide variety covalent solids. One basic assumptions this method been that tight-binding parameters, which describe dependence electronic system upon configuration atoms, simply vary as inverse square appropriate interatomic distance. More recent work, however, shown there are now strong grounds doubting validity 1/d2 approximation, suggested better representation spatial LCAO model Hamiltonian parameters might be obtained from self-consistent bandstructure calculations performed at different lattice constants. purpose paper to assess relative merit these two alternative models by employing them direct determination some dynamical properties silicon, discuss implications results structure analyses within formalism.