  Slater-Condon rules are at the heart of any quantum chemistry method as they
allow to simplify $3N$-dimensional integrals as sums of 3- or 6-dimensional
integrals. In this paper, we propose an efficient implementation of those rules
in order to identify very rapidly which integrals are involved in a matrix
element expressed in the determinant basis set. This implementation takes
advantage of the bit manipulation instructions on x86 architectures that were
introduced in 2008 with the SSE4.2 instruction set. Finding which spin-orbitals
are involved in the calculation of a matrix element doesn't depend on the
number of electrons of the system.
