Synthesis, crystal structure, thermal analysis and dielectric properties of [(C{sub 4}H{sub 9}){sub 4}N]{sub 3}Bi{sub 2}Cl{sub 9} compound
A new organic–inorganic tri-tetrabutylammonium nonachlorobibismuthate(III) compound was prepared. It was found to crystallize in the monoclinic system (P2{sub 1}/n space group) with the following lattice parameters: a=11.32(2) Å, b=22.30(3) Å, c=28.53(2) Å and β=96.52(0)°. The [Bi{sub 2}Cl{sub 9}]{sup 3−} anions are surrounded by six [(C{sub 4}H{sub 9})N]{sup +} cations, forming an octahedral configuration. These octahedra are sharing corners in order to provide the tri-dimensional network cohesion. The differential scanning calorimetry reveals four order-disorder reversible phase transitions located at 214, 238, 434 and 477 K. The Raman and infrared spectra confirm the presence of both cationic [(C{sub 4}H{sub 9})N]{sup +} and anionic [Bi{sub 2}Cl{sub 9}]{sup 3−} parts. The dielectric parameters, real and imaginary dielectric permittivity (ε′ and ε″), and dielectric loss tangent (tg δ), were measured in the frequency range of 209 kHz–5 MHz at different temperatures. The variations of dielectric dispersion (ε') and dielectric absorption (ε″) with frequency show a distribution of relaxation times, which is probably related to the change in the dynamical state of the [(C{sub 4}H{sub 9}){sub 4}N]{sup +} cations and the [Bi{sub 2}Cl{sub 9}]{sup 3−} anions. - Graphical abstract: Projection of the atomic arrangement of the [(C{sub 4}H{sub 9}){sub 4}N]{sub 3}Bi{sub 2}Cl{sub 9} compound along the b axis. - Highlights: • The structure of the (TBA){sub 3}Bi{sub 2}Cl{sub 9} compound was solved and reported. • The cristal belongs to the monoclinic system with P2{sub 1}/n space group. • DSC discloses four order–disorder reversible phases transitions. • The temperature-dependent permittivity ε' and ε″ has been investigated.