  The acquisition of precise and reliable nuclear data is a prerequisite to
success for stellar evolution and nucleosynthesis studies. Core-collapse
simulators find it challenging to generate an explosion from the collapse of
the core of massive stars. It is believed that a better understanding of the
microphysics of core-collapse can lead to successful results. The weak
interaction processes are able to trigger the collapse and control the
lepton-to-baryon ratio ($Y_{e}$) of the core material. It is suggested that the
temporal variation of $Y_{e}$ within the core of a massive star has a pivotal
role to play in the stellar evolution and a fine-tuning of this parameter at
various stages of presupernova evolution is the key to generate an explosion.
During the presupernova evolution of massive stars, isotopes of iron, mainly
$^{54,55,56}$Fe, are considered to be key players in controlling $Y_{e}$ ratio
via electron capture on these nuclide. Recently an improved microscopic
calculation of weak interaction mediated rates for iron isotopes was introduced
using the proton-neutron quasiparticle random phase approximation (pn-QRPA)
theory. The pn-QRPA theory allows a microscopic \textit{state-by-state}
calculation of stellar capture rates which greatly increases the reliability of
calculated rates. The results were suggestive of some fine-tuning of the
$Y_{e}$ ratio during various phases of stellar evolution. Here we present for
the first time the fine-grid calculation of the electron and positron capture
rates on $^{54,55,56}$Fe. Core-collapse simulators may find this calculation
suitable for interpolation purposes and for necessary incorporation in the
stellar evolution codes.
