A cobalt containing mixed-anion uranyl oxidefluoride was synthesized using a mild hydrothermal crystal growth method. The uranyl ions are condensed into a onedimensional chain motif separated by isolated cobalt hexa-aqua centers. The 1-D uranyl material was characterized by singlecrystal and powder X-ray diffraction. The optical, thermal, and magnetic properties were studied and are reported herein. Using the reported composition as a model, a system was derived to predict the dimensionality of hypothetical structures to advance our ability to rationally predict solid-state materials.