Synthesis of Co(hmba)3[CoBr4]×2EtOH crystals was performed according to the procedure in Refs. . Before starting the synthesis, ethanol (EtOH) and ethyl acetate (EtOAc) were dried using molecular sieves for at least 24 h. Then, N,N'-1,6-hexamethylenebis(acetamide) (hmba, ~133 mg) was heated in 1.5 mL of EtOH and 13.5 mL of EtOAc under reflux. At this point, we observed that hmba would only partially dissolve upon reflux and magnetic stirring of this solution.