  Given the low ionization fraction of molecular clouds, ambipolar diffusion is
thought to be an integral process in star formation. However, chemical and
radiative-transfer effects, observational challenges, and the fact that the
ion-neutral drift velocity is inherently very small render a definite detection
of ambipolar diffusion extremely non-trivial. Here, we study the ion-neutral
drift velocity in a suite of chemodynamical, non-ideal magnetohydrodynamic
(MHD), two-dimensional axisymmetric simulations of prestellar cores where we
alter the temperature, cosmic-ray ionization rate, visual extinction,
mass-to-flux ratio, and chemical evolution. Subsequently, we perform a number
of non-local thermodynamic equilibrium (non-LTE) radiative-transfer
calculations considering various idealized and non-idealized scenarios in order
to assess which factor (chemistry, radiative transfer and/or observational
difficulties) is the most challenging to overcome in our efforts to detect the
ion-neutral drift velocity. We find that temperature has a significant effect
in the amplitude of the drift velocity with the coldest modelled cores (T = 6
K) exhibiting drift velocities comparable to the sound speed. Against
expectations, we find that in idealized scenarios (where two species are
perfectly chemically co-evolving) the drift velocity ``survives"
radiative-transfer effects and can in principle be observed. However, we find
that observational challenges and chemical effects can significantly hinder our
view of the ion-neutral drift velocity. Finally, we propose that $\rm{HCN}$ and
$\rm{HCNH^+}$, being chemically co-evolving, could be used in future
observational studies aiming to measure the ion-neutral drift velocity.
