The terms in Eq. 2 account for nuclear-nuclear repulsion, the kinetic energy of electrons, nuclear-electron attraction, electron-electron repulsion and the exchange correlation potential, respectively. In the above equation, Z A , Z B are nuclear charges, R A and R B are positions of nuclei A and B, r represent the electronic coordinates, ψ i are spatial molecular orbitals, and ρ is the electron density. Hybrid GGA functionals include an appropriately scaled exchange term that depends on the occupied orbitals.