  As part of a project to compute improved atomic data for the spectral
modeling of iron K lines, we report extensive calculations and comparisons of
atomic data for K-vacancy states in Fe XXIV. The data sets include: (i) energy
levels, line wavelengths, radiative and Auger rates; (ii) inner-shell electron
impact excitation rates and (iii) fine structure inner-shell photoionization
cross sections. The calculations of energy levels and radiative and Auger rates
have involved a detailed study of orbital representations, core relaxation,
configuration interaction, relativistic corrections, cancellation effects and
semi-empirical corrections. It is shown that a formal treatment of the Breit
interaction is essential to render the important magnetic correlations that
take part in the decay pathways of this ion. As a result, the accuracy of the
present A-values is firmly ranked at better than 10% while that of the Auger
rates at only 15%. The calculations of collisional excitation and
photoionization cross sections take into account the effects of radiation and
spectator Auger dampings. In the former, these effects cause significant
attenuation of resonances leading to a good agreement with a simpler method
where resonances are excluded. In the latter, resonances converging to the K
threshold display symmetric profiles of constant width that causes edge
smearing.
