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Dielectric and Structural Studies of Ba2ReNb3Ti2O15 (BReNTO15,Re=Bi3+,La3+,Nd3+,Sm3+,Gd3+) Tetragonal Tungsten Bronze Structured Ceramics
Published
Author(s)
Igor Levin, M Stennett, I Reaney, G Miles, D I. Woodward, C Kirk, A R. West
Abstract
The structure and dielectric properties of a new family of tetragonal tungsten bronze structured ceramics with the general formula, Ba2ReNb3Ti2O15 (BReNTO15,Re=Bi3+,La3+,Nd3+,Sm3+,Gd3+) have been investigated. BLNTO15 Tmax -100 C) and BBNTO15 (Tmax -80 C) exhibited relaxor-like dielectric behaviour with the maximum dielectric constants observed at Tm-100 C and Tm-80 C, respectively. In contrast, BNNTO15 (Curie temperature, Tc 165 C), BSNTO15 (Tc 250 C), and BGNTO15 (Tc 320 C) were ordinary ferroelectrics. The Tm/Tc ratio increased with decreasing radius of the Re ion. Room-temperature X-ray powder diffraction patterns of all the compounds could be indexed according to a prototype P4/mbm (or P4bm) space group with lattice parameters a12.4 A and c4 A. However electron diffraction revealed that both BLNTO15 and BBNTO15 phases exhibit an incommensurate modulation, whereas BNNTO15, BSNTO15 and BGNTO15 feature an orthorhombic superstructure with lattice parameters abaTTB 2 and c2cTTB.
Levin, I.
, Stennett, M.
, Reaney, I.
, Miles, G.
, Woodward, D.
, Kirk, C.
and West, A.
(2017),
Dielectric and Structural Studies of Ba<sub>2</sub>ReNb<sub>3</sub>Ti<sub>2</sub>O<sub>15</sub> (BReNTO<sub>15</sub>,Re=Bi<sup>3+</sup>,La<sup>3+</sup>,Nd<sup>3+</sup>,Sm<sup>3+</sup>,Gd<sup>3+</sup>) Tetragonal Tungsten Bronze Structured Ceramics, Journal of Applied Physics
(Accessed October 8, 2025)