Related Experiment Video
Updated: Jun 15, 2025

Epitaxial Growth of Perovskite Strontium Titanate on Germanium via Atomic Layer Deposition
Published on: July 26, 2016
Atomic Layer Engineering of Ferroelectricity in Dion-Jacobson Perovskites
Shu Morita1, Daisuke Urushihara2, Keita Nishibashi1
1Department of Materials Chemistry & Institute of Materials and Systems for Sustainability (IMaSS), Nagoya University, Nagoya 464-8601, Japan.
Abstract:
Recent advances in "hybrid-improper" ferroelectricity in Dion-Jacobson (DJ)-type layered perovskites have caused renewed interest in the search for new ferroelectrics. Here, we present an approach for the tailored synthesis of a new homologous series of DJ-type layered perovskites Cs(Bi2Sr-3)(Ti-1Nb)O3. Starting from CsBi2Ti2NbO10 (n = 3), higher-order homologous phases with n = 4 and 5 were successfully synthesized by repeated solid-state calcination with SrTiO3. Characterizations by X-ray diffraction, electron diffraction, transmission electron microscopy, Raman scattering, and second harmonic generation showed the detailed structural features in Cs(Bi2Sr-3)(Ti-1Nb)O3, and the polar structures could be stabilized by proper or hybrid-improper ferroelectricity, depending on the odd or even number of the perovskite layers. Our results provide important insights into the competition between the different mechanisms and the consequences of the ferroelectric properties in homologous layered perovskites.
Related Concept Videos
Ferromagnetism
Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Dielectric Polarization in a Capacitor
Valence Bond Theory
Trends in Lattice Energy: Ion Size and Charge
Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...

