  The rich information of electron energy-loss spectroscopy (EELS) comes from
the complex inelastic scattering process whereby fast electrons transfer energy
and momentum to atoms, exciting bound electrons from their ground states to
higher unoccupied states. To quantify EELS, the common practice is to compare
the cross-sections integrated within an energy window or fit the observed
spectrum with theoretical differential cross-sections calculated from a
generalized oscillator strength (GOS) database with experimental parameters.
The previous Hartree-Fock-based and DFT-based GOS are calculated from
Schr\"odinger's solution of atomic orbitals, which does not include the full
relativistic effects. Here, we attempt to go beyond the limitations of the
Schr\"odinger solution in the GOS tabulation by including the full relativistic
effects using the Dirac equation within the local density approximation, which
is particularly important for core-shell electrons of heavy elements with
strong spin-orbit coupling. This has been done for all elements in the periodic
table (up to Z = 118) for all possible excitation edges using modern computing
capabilities and parallelization algorithms. The relativistic effects of fast
incoming electrons were included to calculate cross-sections that are specific
to the acceleration voltage. We make these tabulated GOS available under an
open-source license to the benefit of both academic users as well as allowing
integration into commercial solutions.
