Repozytorium
Wyszukaj
Kolekcje
Inne
Ferroelectricity in ethylammonium bismuth-based organic–inorganic hybrid: (C2H5NH3)2[BiBr5].
Autorzy
Rok wydania
2020
Czasopismo
Numer woluminu
59
Strony
3417-3427
DOI
10.1021/acs.inorgchem.9b03193
Kolekcja
Język
Angielski
Typ publikacji
Artykuł
The (C2H5NH3)2[BiBr5] (EBB) crystals adopt the one-dimensional (1D) polymeric anionic form [BiBr5]∞2-, which is preferred by halobismuthates(III) exhibiting polar properties and realized in R2MX5 stoichiometry. Differential scanning calorimetry and dilatometric measurements reveal reversible structural phase transitions: at 160 K (phase I → phase II) and 120 K (phase II → phase III). The resolved crystal structures of EBB show the centrosymmetric space group in phase I (Aeam), polar (Pca21) in phase II, and polar (Aea2) in phase III. The presence of dielectric hysteresis loops in phases II and III evidence ferroelectric properties. The dielectric response [ε*(ω,T)] of EBB close to 160 K is characteristic of ferroelectrics with a critical slowing down process. The molecular mechanism of a paraelectric-ferroelectric phase transition at 160 K is explained as "order-disorder" (assigned to the dynamics of the ethylammonium cations) and dominating "displacive" (related to strong distortion of the 1D anionic network). The optical band gap obtained from UV-vis measurements is about 2.6 eV. The conduction band minimum is formed by the hybridized Bi 6p and Br 4p states. An analysis of the CSD results for haloantimonates(III) and halobismuthates(III) ferroelectrics characterized by [MX4]-, [M2X9]3-, [MX5]2-, and [M2X11]5- anions is given.
Słowa kluczowe
Amines, Insulators, Phase transitions, Cations, Polarization
Adres publiczny
http://dx.doi.org/10.1021/acs.inorgchem.9b03193
Strona internetowa wydawcy
Podobne publikacje
Advances and property investigations of an organic–inorganic ferroelectric: (diisopropylammonium)2[CdBr4]
Rok Magdalena, Starynowicz Przemysław, Ciżman Agnieszka, Zaręba Jan K., Piecha-Bisiorek Anna, Bator Grażyna , Jakubas Ryszard
0D Bismuth(III)-Based Hybrid Ferroelectric: Tris(acetamidinium) Hexabromobismuthate(III)
Mencel Klaudia, Kinzhybalo Vasyl, Jakubas Ryszard, Zaręba Jan K., Szklarz Przemysław, Durlak Piotr, Drozd Marek, Piecha-Bisiorek Anna
Progressive Structural Complexity in Ferroelectric 1,2,4-Triazolium Hexabromoantimonate(III): Interplay of "Order-Disorder" and "Displacive" Contributions to the Structural Phase Transitions
Chański Michał, Białońska Agata, Jakubas Ryszard, Rok Magdalena, Zaręba Jan K., Janicki Rafał, Durlak Piotr, Piecha-Bisiorek Anna