Three-dimensional Schrödinger equation, single-electron atom, spin-orbit coupling, relativistic corrections, fine structure, spectroscopic classification, hyperfine structure, radiative transitions and selection rules, Pauli principle and periodic table, multi-electron atoms, Hartree-Fock field, LS and j-j coupling, Zeeman effect, chemical bonding, energy states of molecules, van der Waals forces, crystals, band structure of solids.