Dielectric-Optical Switches: Photoluminescent, EPR, and Magnetic Studies on Organic-Inorganic Hybrid (azetidinium)2MnBr4

A new organic-inorganic hybrid, AZEMnBr, has been synthesized and characterized. The thermal differential scanning calorimetry, differentialthermal analysis, and thermogravimetric analyses indicate one structural phasetransition (PT) at 346 and 349 K, on cooling and heating, respectively.AZEMnBrcrystallizes at 365 K in the orthorhombic,Pnma, structure, which transforms tomonoclinicP21/nat 200 K. Due to the X-ray diffraction studies, the anionicMnBr42-moiety is discrete. The azetidinium cations show dynamical disorder inthe high-temperature phase. In the proposed structural PT, the mechanism isclassified as an order-disorder type. The structural changes affect the dielectricresponse. In this paper, the multiple switches between low- and high- dielectricstates are presented. In addition, it was also observed that the crystal possesses amutation offluorescent properties between phase ON and OFF in the PT's pointvicinity. We also demonstrate that EPR spectroscopy effectively detects PTs instructurally diverse Mn(II) complexes.AZEMnBrcompounds show DC magnetic data consistent with theS= 5/2 spin system withsmall zero-field splitting, which was confirmed by EPR measurements and slow magnetic relaxation under the moderate DCmagneticfield typical for a single-ion magnet behavior. Given the above, this organic-inorganic hybrid can be considered a rareexample of multifunctional materials that exhibit dielectric, optical, and magnetic activity

Automated summary

A new organic-inorganic hybrid material, AZEMnBr, has been synthesized and characterized, showing structural phase transition, dielectric response, fluorescent properties, and magnetic behavior. This material exhibits multifunctional properties.