Crystal structure and energy transfer of trans-RSSR-[CrCl2(cyclam)]3[Cr(CN)6] · 14H2O

Within the study of the counterion effect on the optical properties of the cation in trans-RSSR-[CrCl2(cyclam)]2ZnCl4, we synthesised and characterised by spectroscopic techniques and X-ray crystallography the trans-RSSR-[CrCl2(cyclam)]3[Cr(CN)6] · 14H2O (1) complex. The X-ray structural analysis of 1 shows that the crystal network involves hydrogen bonding distances of (N(1)H(1)⋯N(27)C(26) 2.29(7) and N(18)H(18)⋯N(27)C(26) 2.33(6) Å, and distances between cation and anion: Cr(1)⋯Cr(3) and Cr(2)⋯Cr(3) were found to be 6.999 and 6.924 Å. The lifetime emission for Cr(1)(2) was found to be 17 μs, while the lifetime for Cr(3) was found to be 100 μs. These values are a consequence of an energy transfer process. This energy transfer through the supramolecular interactions of the cation and anion via hydrogen bonding is probably responsible for the optical properties shown by 1 in the solid state.