Separately, 12.7 mg of 18-crown-6 was dissolved in 3 mL of cold (-30 °C) toluene to create a stock solution and then stored in a glovebox freezer at -30 °C to maintain the temperature of the solution. Once both solutions were prepared and chilled to -30 °C, they were removed from the glovebox freezer. A disposable glass pipette was used to transfer 3 drops of the toluene solution containing 18-crown-6 to the DME solution containing DyI2. Neither solution was stirred. Both solutions were then carefully (avoiding agitation of the solution) replaced in the glovebox freezer to maintain a solution temperature of -30 °C. Both solutions were allowed to sit in the freezer for 5 minutes untouched. Then, the solutions were carefully removed from the freezer to avoid agitation, and 3 drops of the toluene stock solution containing 18-crown-6 was again added to the solution containing DyI2. This process was repeated continually avoiding agitation of the DyI2 solution at all costs. Additions of the 18-crown-6 stock solution yielded a dark brownish-green precipitate almost immediately. After the slow, dropwise addition of almost half of the stock solution described previously, dark green microcrystals began to form on the walls of the glass scintillation vial. Slow, dropwise addition of the ligand solution sometimes resulted in crystals of Dy(18-crown-6)I2 large enough for single-crystal x-ray diffraction studies, but total crystalline yield was low (< 20%). Further characterization and interpretation of Dy(18-crown-6)I2 will reported elsewhere, but the crystal structure is crucial to the bond length comparisons for Cf(18crown-6)I2.