Synthesis Process and Magnetic Characterization of the Novel Aurivillius Ferroelectric Material ${\hbox {Bi}}_{4}{\hbox {Gd}}_{2}{\hbox {Ti}}_{3}{\hbox {Fe}}_{2}{\hbox {O}}_{18}$

Comprehensive research of the synthesis process by high temperature solid-state reaction method, the crystal structure characterization, and the magnetic properties of the Aurivillius type Bi-layered perovskite-like structure Bi₄Gd₂Ti₃Fe₂O₁₈ was undertaken. Patterns of X-ray diffraction measurements and Rietveld analysis allow us to establish that this material crystallizes in a pseudo-orthorhombic structure which belongs to the I2cm (#46) space group. The crystal structure is characterized by Bi₂O₂ layers and complex perovskite-like structures, with quintuplets octahedra TiO₆, and the Bi-cations occupying the A-site. The unit-cell parameters are given by a=5.5234(2) Å, b=5.5312(2) Å, and c=52.5642(2) Å, the angles are α = β = γ = 90.0^°, and unit-cell volume V=1605.9(1) ų. Magnetic properties found from the fit of Curie-Weiss law to the curves of magnetic susceptibility χ as a function of temperature show that the Bi-layered Aurivillius material Bi₄Gd₂Ti₃Fe₂O₁₈ behaves as a paramagnetic material with evidence of ferromagnetic contributions, and allows for determining the Curie constant, given by C=0.014 emuK/mol, effective magnetic moment of P_effμ_B=7.78μ_B, and temperature independent susceptibility χ_o=0.0064 emu/mol. Field dependence of magnetization proves strongly paramagnetic behavior of the Bi-layered Bi₄Gd₂Ti₃Fe₂O₁₈.