Synthesis, characterization, and phase transition of an inorganic–organic hybrid compound, [(3-nitroanilinium+)(18-crown-6)][IO4−](CH3OH)

Abstract

A novel inorganic–organic hybrid supramolecular compound, [(3-nitroanilinium+)(18-crown-6)][IO4−](CH3OH) (1), was discovered as phase-transition materials displaying dielectric anomalous behaviors. The yellow block crystal formed by N–H···O hydrogen bonding that made contact through the cavity of 18-crown-6 was characterized by single-crystal X-ray diffraction, elemental analysis, infrared analysis, thermogravimetric analysis, differential scanning calorimetry, and potential-energy calculations. Differential scanning calorimetry measurements indicate that the compound experiences a reversible phase transition at around 220K. Temperature-dependent dielectric measurements further confirm the phase transitions. Potential-energy calculations demonstrate that the phase transition occurs due to the molecular order–disorder rotation of CH3OH, whereas the space grouping of the crystal remains unchanged.