This proposal forms part of an exploratory study of new mixed anion coordination compounds. We have prepared a family of oxalate-fluorides, which are anticipated to have frustrated magnetic properties due to competing interactions mediated via the oxalate and fluoride ligands. Two of these compounds have composition CsM(C2O4)F, where M = Co or Fe. They have a simple crystal structure based on 'rectangular' layers, where the sides of the rectangle represent different chemical 'bridges' between magnetic centres: fluoride or oxalate bridges. They show similar, but distinct magnetic properties, with evidence for low-dimensional magnetic interactions, followed at lower temperature, by a more abrupt magnetic anomaly for the Co compound. We aim to explore the possibly ordered magnetic state of these compounds at lower temperature.