The total Hamiltonian of the Breit equation, sometimes called the Dirac–Coulomb–Breit Hamiltonian (H DCB) can be decomposed into the following practical energy operators for electrons in electric and magnetic fields (also called the Breit–Pauli Hamiltonian), which have well-defined meanings in the interaction of molecules with magnetic fields (for instance for nuclear magnetic resonance): B ^ ^ i j = H ^ ^ 0 + H ^ ^ 1 + ⋯ ⋯ + H ^ ^ 6 , in which the consecutive partial operators are: