Approximation theory 2 Atoms 2 Calculations 2 Density functional theory 2 Electronic structure 2 Electrostatics 2 Finite difference method 2 Finite difference pseudopotential 2 Genetic algorithms 2 Isomers 2 Local density approximation method 2 Molecular dynamics 2 Permittivity 2 Probability density function 2 Silicon 2 Silicon isomers 2 Static dipole polarizability 2 Statistical methods 2