The structure and switchable dielectric properties of a dabco complex with chromium chloride.

We report a metal-organic material of the following formula [DabcoH22+]·CrCl3(H2O)3·2(Cl-) (DabcoH22+ = C6H14N22+, diprotonated 1,4-diazabicyclo[2.2.2]octanium). This compound exhibits a dielectric anomaly, which is attributed to the rotatory fluctuation of the Dabco molecule. The complementary results of single-crystal X-ray diffraction, DSC, dielectric, NMR and Raman spectroscopy provide information about the general mechanisms of the phase transition, which results from the ordering of the DabcoH22+ molecules. The reversibility of dielectric switching with no observable attenuation of the dielectric signal during multiple cycling is observed. The dielectric switching characteristic of the crystal makes it an interesting material for potential application in smart devices.