  The bands of diatomic molecules are important abundance indicators,
especially in metal-poor stars, where they are still measurable in metallicity
regimes where the atomic lines of their constituting metallic elements have
become vanishingly small. In order to use them for abundance determinations it
is imperative to understand the formation of these bands. In this contribution
we report on our results obtained using CO5BOLD hydrodynamical simulations.
Some effects that are qualitatively different from what found in 1D
computations are highlighted. Due to the large number of lines that form the
bands, their spectrum synthesis is computationally challenging. We discuss some
of the computational strategies we employed to parallelise the computation and
possible future developments.
