ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

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

Rahma Jabbar, Francois Michaud, and Slaheddine Kamoun

Universite´ de Sfax, Sfax, Tunisia

E-mail: slah.kamoun@enis.rnu.tn

Abstract: 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 E_g = 2.20 eV was estimated by diffuse reflection spectroscopy (DRS) investigation.

Keywords: Structure ; Ferroelectric relaxor ; Vogel–Fulcher model ; Modulus ; Conductivity 

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-019-00691-3

Chemical Papers 73 (6) 1389–1399 (2019)