Our calculations not only allow us to predict the interaction energies, but also to explore the electronic structure of this material (Fig. ). The predicted thermal band gap is approximately 1.2 eV, and the projection of the DOS onto local orbitals shows that the top of the valence band is broadly Cr and Cl based, whilst the organic linker pym states are the bottom of the conduction band. This can also be observed in the frontier orbitals, where the HOMO resembles the Cr d z 2 orbital antibonding with Cl p orbitals and the LUMO is an antibonding π molecular orbital with a single additional node, suggesting that the lowest lying excitations will be of MLCT character. The spin density is predominantly around the Cr, however, there is significant density on both Cl and pym ligands (Fig. ). Notably, the spin density on pym appears to be primarily of π character, and alternates in sign round the ring (Fig. ).