First-principles study of the ferroelectric Aurivillius phase Bi<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mrow /><mml:mn>2</mml:mn></mml:msub></mml:math>WO<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mrow /><mml:mn>6</mml:mn></mml:msub></mml:math>

Djani, Hania; Bousquet, Éric; Kellou, A.; Ghosez, Philippe

doi:10.1103/physrevb.86.054107

Cited by 54 publications

(36 citation statements)

References 33 publications

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“…The reectivity saturates to unity because our formalism neglects the damping of the phonon modes. 34 The experimental spectrum, recorded at room temperature and using the 633 nm laser line excitation, is also reported in this gure. The eigenvectors of the polar TO modes do not necessarily correspond to those of their corresponding LO modes due to the long-range Coulomb interactions.…”

Section: Infrared and Raman Spectroscopiesmentioning

confidence: 99%

Revisited phonon assignment and electro-mechanical properties of chromium disilicide

et al. 2015

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We report a complete study of the lattice dynamics, dielectric, elastic and piezoelectric properties of hexagonal semiconducting chromium disilicide (CrSi 2 ). From a combined experimental and theoretical study, we have revisited the phonon mode assignments at the zone-center, so that the contradictions met in previous experimental studies between 250 and 300 cm À1 are now explained and understood.We found that the temperature dependence of the Raman frequencies is mainly due to an implicit volume contribution and related to the large Grüneisen parameter. This explains why CrSi 2 has a moderate thermal conductivity although its Debye temperature is quite large. Optic and static dielectric constants have also been analyzed and discussed. The elastic constants of CrSi 2 are large, but this compound is quite brittle. In addition, the relatively low Poisson coefficient associated to the large negative Cauchy pressure of CrSi 2 indicate the angular nature of its bonding. The calculation of its piezoelectric coefficient shows a sizable value with a magnitude similar to that reported for a-quartz.

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Section: Infrared and Raman Spectroscopiesmentioning

confidence: 99%

Revisited phonon assignment and electro-mechanical properties of chromium disilicide

et al. 2015

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“…Many ferroelectric oxides form ABO 3 perovskites with a three-dimensional network of corner-sharing octahedra [5]. The connectivity of octahedra can be modified to form a layered structure [6][7][8][9][10][11][12][13]. The Ruddlesden-Popper series, A 2 [A n−1 B n O 3n−1 ] is one of the most well-known examples [6,7].…”

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confidence: 99%

“…Two other series of layered perovskites are the Dion-Jacobson series [8,9] and the Aurivillius series [10,11] with the chemical formulas, A[A n−1 B n O 3n+1 ] and Bi 2 O 2 [A n−1 B n O 3n+1 ], respectively. In a layered perovskite oxide, many lead-free ferroelectric candidates have been proposed [2,12,13].…”

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confidence: 99%

Octahedral tilting and ferroelectricity in RbANb2O7(A = Bi, Nd) from first principles

Sim

Kim

2014

Phys. Rev. B

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The effects of octahedral tilting of RbANb 2 O 7 (A = Bi, Nd) compounds was studied using density-functional theory. In this compound, the structural phase transition was correlated with two octahedral tilting modes (a − a − c 0 tilting and a 0 a 0 c + tilting), and the magnitude of the octahedral tilting mode was analyzed in the optimized structure. The theoretical results correlated well with the recent experimental results on the ferroelectricity of RbBiNb 2 O 7 . The hybrid improper ferroelectricity resulting from the coupling of two octahedral tilting modes and off-center displacement mode was analyzed by group theory and symmetry mode analysis. The detailed relationship of the tilting modes to the structural phase transition and the detailed physical properties of ferroelectricity are also presented.

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“…Schematic illustration of atomic motions associated to the unstable phonon modes of the I4/mmm phase of Bi2W2O9 (at high-symmetry points of the Brillouin zone). Rigid-layer modes (RL modes) are related to a nearly rigid motion of the [Bi2O2] +2 layer with respect to the perovskite block [6,16]. For modes involving polar and antipolar cationic displacements, oxygen atoms motions are omitted for clarity.…”

Section: Characterisationmentioning

confidence: 99%

Bi2W2O9: A potentially antiferroelectric Aurivillius phase

et al. 2020

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Ferroelectric tungsten-based Aurivillius oxides are naturally stable superlattice structures, in which A-site deficient perovskite blocks [WnO3n+1] −2 (n = 1, 2, 3, ...) interleave with fluorite-like bismuth oxide layers [Bi2O2] +2 along the c-axis. In the n = 2 Bi2W2O9 phase, an in-plane antipolar distortion dominates but there has been controversy as to the ground state symmetry. Here we show, using a combination of first-principles density functional theory calculations and experiments, that the ground state is a non-polar phase of P nab symmetry. We explore the energetics of metastable phases and the potential for antiferroelectricity in this n = 2 Aurivillius phase. arXiv:2003.00486v1 [cond-mat.mtrl-sci]

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First-principles study of the ferroelectric Aurivillius phase Bi2WO6

Cited by 54 publications

References 33 publications

Revisited phonon assignment and electro-mechanical properties of chromium disilicide

Revisited phonon assignment and electro-mechanical properties of chromium disilicide

Octahedral tilting and ferroelectricity in RbANb2O7(A = Bi, Nd) from first principles

Bi2W2O9: A potentially antiferroelectric Aurivillius phase

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