Clausius-Mossotti equation; Cohesive property; Dielectric functions; Dispersion coefficient; Functionals; GaAs; Hirshfeld partitioning; Polarizabilities; Time dependent density functional theory; Van der Waals (vdW) energies; Van Der Waals interactions; Dielectric materials; Gallium arsenide; Germanium; Polarization; Semiconducting gallium; Semiconducting silicon; Semiconducting silicon compounds; Sodium chloride; Time varying systems; Van der Waals forces; Wave functions; Density functional theory