The Coulomb operator, named after Charles-Augustin de Coulomb, is a quantum mechanical operator used in the field of quantum chemistry. Specifically, it is a term found in the Fock operator. It is defined as:
where
is the one-electron Coulomb operator defining the repulsion resulting from electron j,
f(1) is a one-electron wavefunction being acted upon by the Coulomb operator,
is the one-electron wavefunction of the jth electron,
is the distance between electrons 1 and 2.