Principles of Molecular Orbital Theory
In molecules, atomic orbitals combine to form molecular orbitals which surround the molecule. Similar to atomic orbitals, molecular orbitals are wave functions giving the probability of finding an electron in certain regions of a molecule. Each molecular orbital can only have 2 electrons, each with an opposite spin. Each molecular orbital can only have 2 electrons, each with an opposite spin. Once you have the molecular orbitals and their energy ordering the ground state configuration is found by applying the Pauli principle, the aufbau principle and Hund's rule just as with atoms.