The "Hemi Orange" used on the concept is a "pearlcoat" paint. It changes hues depending on the direction and intensity of the light hitting it. DuPont makes "Chromalusion" paint which does something very similar, but more extreme. A car painted Chromalusion Gold can appear any color from purple to brown, depending on the lighting. A more mild effect is achieved with pearlcoat, so the Hemi Orange could appear anywhere from Bronze to Orange to almost Yellow - and anything in between depending on the angle it's viewed from.

BTW- Pearlcoat paints are available at a "premium charge". You'll notice that in the "Build my own" option on Dodge's website.
Did I mention DuPont's "Chromalusion" paint costs (last time I looked) around $2,500.00 a gallon?