is confined to studies of the first-row transition metals and their complexes with a small number of ligands. Exploring the chemistries of underexploited metal cations and molecular ligands thus offers the opportunity to produce new materials with properties very different from the current exemplars. Thiocyanate (SCN -) is a particularly interesting candidate small ligand for the assembly of molecular frameworks, as its chemical softness allows easy access to a wider range of coordination chemistry. In addition, thiocyanate based materials often have strong optical absorption, for example the terpyridine Ru(SCN) 3 complexes used in dye-sensitised solar cells, and can contain reasonably strong magnetic interactions. Despite the potential of this ligand, there are relatively few reported structures of three dimensional thiocyanate based frameworks, of which only two are perovskites, CsCd(SCN) 3 and the double perovskite (NH 4 ) 2 CdNi(SCN) 6 . In addition, there are no known thiocyanate analogues of the Prussian blue structured (i.e. A-site vacancy double perovskite) cyanides.