  We focus on studying the opacity of iron, chromium, and nickel plasmas at
conditions relevant to experiments carried out at Sandia National Laboratories
[J. E. Bailey et al., Nature 517, 56 (2015)]. We calculate the photo-absorption
cross-sections and subsequent opacity for plasmas using linear response
time-dependent density functional theory (TD-DFT). Our results indicate that
the physics of channel mixing accounted for in linear response TD-DFT leads to
an increase in the opacity in the bound-free quasi-continuum, where the Sandia
experiments indicate that models under-predict iron opacity. However, the
increase seen in our calculations is only in the range of 5-10%. Further, we do
not see any change in this trend for chromium and nickel. This behavior
indicates that channel mixing effects do not explain the trends in opacity
observed in the Sandia experiments.
