Compound 2 crystallized as fragile long needles which fractured easily when touched with an acupuncture needle. The crystal could not be cut easily without destroying its integrity so a crystal larger than the X-ray beam was used. Although the cage and counter ions could be identified it was not possible to identify solvent molecules, amounting to some 216 electrons per unit cell. This therefore cannot be included in the total formula, since the identity of the solvent could not be established reliably, and is reported instead as "+ solvent". The SQUEEZE routine of PLATON was used to handle electron density pertaining to the solvent. This triggers checkCIF alerts. The MeCN ligand was refined using an isotropic model. The value of Z' is 0.5. This means that only half of the formula unit is present in the asymmetric unit, with the other half consisting of symmetry equivalent atoms.