Synthesis and investigation of structural, optical, dielectric and electronic properties of a new hybrid: [C13H21N2O2](Cd(SCN)3)

A new ferroelectric relaxor: [C13H21N2O2](Cd(SCN)3) procainium tris(thiocyanato) cadmiate(II) was synthesized and studied by single-crystal XRD. This compound crystallizes in the orthorhombic system with acentric space group Pna21. The crystal structure is formed of discrete ionic entities (C13H21N2O2)+ and [Cd(SCN)3]−. The cadmium atom has 3N3S hexa coordinated octahedral geometry. The sulfur atoms and the nitrogen atoms are in facial mode (fac). Each pair of cadmium atoms is triply bridged by μ-1,3-SCN–bridge. Consequently, a linear polymeric chain is formed. The procainium cations are bonded to these chains by hydrogen-bonding contacts and π–ring interaction. DSC measurement shows that this compound exhibits a diffuse ferro–paraelectric phase transition around 356 K. Dielectric study exhibits a relaxor behavior characterized by the transition temperature shifts toward higher temperature with the rise of frequency. This behavior was validated by the Vogel–Fulcher relationship and the modified Curie–Weiss law. The diffuseness parameter was γ = 1.96. The optical band gap Eg = 2.20 eV was estimated by diffuse reflection spectroscopy (DRS) investigation.