Records |
Author |
Morozov, V.A.; Bertha, A.; Meert, K.W.; Van Rompaey, S.; Batuk, D.; Martinez, G.T.; Van Aert, S.; Smet, P.F.; Raskina, M.V.; Poelman, D.; Abakumov, A.M.; Hadermann, J.; |
Title |
Incommensurate modulation and luminescence in the CaGd2(1-x)Eu2x(MoO4)4(1-y)(WO)4y (0\leq x\leq1, 0\leq y\leq1) red phosphors |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
25 |
Issue |
21 |
Pages |
4387-4395 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Scheelite related compounds (A',A '') [(B',B '')O-4], with B', B '' = W and/or Mo are promising new light-emitting materials for photonic applications, including phosphor converted LEDs (light-emitting diodes). In this paper, the creation and ordering of A-cation vacancies and the effect of cation substitutions in the scheelite-type framework are investigated as a factor for controlling the scheelite-type structure and luminescent properties. CaGd2(1-x)Eu2x(MoO4)(4(1-y))(WO4)(4y) (0 <= x <= 1, 0 <= y <= 1) solid solutions with scheelite-type structure were synthesized by a solid state method, and their structures were investigated using a combination of transmission electron microscopy techniques and powder X-ray diffraction. Within this series all complex molybdenum oxides have (3 + 2)D incommensurately modulated structures with superspace group I4(1)/a(alpha,beta,0)00(-beta,alpha,0)00, while the structures of all tungstates are (3 + 1)D incommensurately modulated with superspace group I2/b(alpha beta 0)00. In both cases the modulation arises because of cation-vacancy ordering at the A site. The prominent structural motif is formed by columns of A-site vacancies running along the c-axis. These vacant columns occur in rows of two or three aligned along the [110] direction of the scheelite subcell. The replacement of the smaller Gd3+ by the larger Eu3+ at the A-sublattice does not affect the nature of the incommensurate modulation, but an increasing replacement of Mo6+ by W6+ switches the modulation from (3 + 2)D to (3 + 1)D regime. Thus, these solid solutions can be considered as a model system where the incommensurate modulation can be monitored as a function of cation nature while the number of cation vacancies at the A sites remain constant upon the isovalent cation replacement. All compounds' luminescent properties were measured, and the optical properties were related to the structural properties of the materials. CaGd2(1-x)(MoO4)(4(1-y))(WO4)(4y) phosphors emit intense red light dominated by the D-5(0)-F-7(2) transition at 612 nm, along with other transitions from the D-5(1) and D-5(0) excited states. The intensity of the 5D0-7F2 transition reaches a maximum at x = 0.5 for y = 0 and 1. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000327045000030 |
Publication Date |
2013-09-24 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
63 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 9.466; 2013 IF: 8.535 |
Call Number |
UA @ lucian @ c:irua:112776 |
Serial |
1594 |
Permanent link to this record |
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Author |
Batuk, M.; Batuk, D.; Tsirlin, A.A.; Filimonov, D.S.; Sheptyakov, D.V.; Frontzek, M.; Hadermann, J.; Abakumov, A.M. |
Title |
Layered oxychlorides [PbBiO2]An+1BnO3n-1Cl2(A = Pb/Bi, B = Fe/Ti) : intergrowth of the hematophanite and sillen phases |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
27 |
Issue |
27 |
Pages |
2946-2956 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
New layered structures corresponding to the general formula [PbBiO2]A(n+1)B(n)O(3n-1)Cl(2) Were prepared. Pb5BiFe3O10Cl2 (n = 3) and Pb5Bi2Fe4O13Cl2 (n = 4) are built as a stacking of truncated A(n+1)B(n)O(3n-1) perovskite blocks and alpha-PbO-type [A(2)O(2)](2+) (A = Pb, Bi) blocks combined with chlorine sheets. The alternation of these structural blocks can be represented as an intergrowth between the hematophanite and Sullen-type structural blocks. The crystal and-Magnetic structures of Pb5BiFe3O10Cl2 and Pb5Bi2Fe4O13Cl2 were investigated in the temperature range of 1.5-700 K using X-ray and neutron powder diffraction, transmission electron microscopy and Fe-57 Mossbauer spectroscopy. Both compounds crystallize in the I4/mmm space group with the unit cell parameters a approximate to a(p) approximate to 3.92 angstrom (a unit-cell parameter of the perovskite-structure), c approximate to 43.0 angstrom for the n = 3 member and c approximate to 53.5 angstrom for the n = 4 member. Despite the large separation between the slabs containing the Fe3+ ions (nearly 14 angstrom), long-range antiferromagnetic order sets in below similar to 600 K with the G-type arrangement of the Fe magnetic moments aligned along the c-axis. The possibility of mixing d(0) and d(n) cations at the B sublattice of these structures was also demonstrated by preparing the Ti-substituted n = 4 member Pb6BiFe3TiO13Cl2. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000353865800028 |
Publication Date |
2015-03-26 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
11 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 9.466; 2015 IF: 8.354 |
Call Number |
c:irua:126060 |
Serial |
1807 |
Permanent link to this record |
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Author |
Dachraoui, W.; Hadermann, J.; Abakumov, A.M.; Tsirlin, A.A.; Batuk, D.; Glazyrin, K.; McCammon, C.; Dubrovinsky, L.; Van Tendeloo, G. |
Title |
Local oxygen-vacancy ordering and twinned octahedral tilting pattern in the Bi0.81Pb0.19FeO2.905 cubic perovskite |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
24 |
Issue |
7 |
Pages |
1378-1385 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The structure of Bi0.81Pb0.19FeO2.905 was investigated on different length scales using a combination of electron diffraction, high-resolution scanning transmission electron microscopy, synchrotron X-ray powder diffraction, and Mössbauer spectroscopy. In the 80300 K temperature range, the average crystal structure of Bi0.81Pb0.19FeO2.905 is a cubic Pm3̅m perovskite with a = 3.95368(3) Å at T = 300 K. The (Pb2+, Bi3+) cations and O2 anions are randomly displaced along the 110 cubic directions, indicating the steric activity of the lone pair on the Pb2+ and Bi3+ cations and a tilting distortion of the perovskite framework. The charge imbalance induced by the heterovalent Bi3+ → Pb2+ substitution is compensated by the formation of oxygen vacancies preserving the trivalent state of the Fe cations. On a short scale, oxygen vacancies are located in anion-deficient (FeO1.25) layers that are approximately 6 perovskite unit cells apart and transform every sixth layer of the FeO6 octahedra into a layer with a 1:1 mixture of corner-sharing FeO4 tetrahedra and FeO5 tetragonal pyramids. The anion-deficient layers act as twin planes for the octahedral tilting pattern of adjacent perovskite blocks. They effectively randomize the octahedral tilting and prevent the cooperative distortion of the perovskite framework. The disorder in the anion sublattice impedes cooperative interactions of the local dipoles induced by the off-center displacements of the Pb and Bi cations. Magnetic susceptibility measurements evidence the antiferromagnetic ordering in Bi0.81Pb0.19FeO2.905 at low temperatures. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000302487500018 |
Publication Date |
2012-03-13 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
27 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 9.466; 2012 IF: 8.238 |
Call Number |
UA @ lucian @ c:irua:97389 |
Serial |
1829 |
Permanent link to this record |
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Author |
Batuk, D.; Batuk, M.; Morozov, V.A.; Meert, K.W.; Smet, P.F.; Poelman, D.; Abakumov, A.M.; Hadermann, J. |
Title |
Effect of cation vacancies on the crystal structure and luminescent properties of Ca(0.85-1.5x)Gd(x)Eu(0.1)_(0.05+0.5x)WO(4) (0<x<0.567) scheelite-based red phosphors |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Journal of alloys and compounds |
Abbreviated Journal |
J Alloy Compd |
Volume |
706 |
Issue |
706 |
Pages |
358-369 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The Ca0.85-1.5xGdxEu0.1_0.05-0.5xWO4 (0 < x < 0.567) series of cation-deficient scheelites is investigated to unveil the influence of the cation vacancies on the crystal structure and luminescent properties. The concentration of the vacancies is varied by the heterovalent substitution of Gd3+ for Ca2+, keeping the concentration of the Eu3+ luminescent centers constant in all compounds of the series. The crystal structure of the materials is studied using a combination of transmission electron microscopy and synchrotron X-ray powder diffraction. At low vacancy concentration (x = 0.1, 0.2), cations and cation vacancies are randomly distributed in the structure, and the materials preserve the I41/a symmetry of the parent scheelite structure [x = 0.1: a = 5.25151(1) Å, c = 11.39479(2) Å; x = 0.2: a = 5.25042(1) Å, c = 11.41335(2) Å]. At higher concentration, the cation-vacancy ordering gives rise to incommensurately modulated structures. The x = 0.3 structure has a (3 + 2)D tetragonal symmetry [superspace group I41/a(a,b,0)00(-b,a,0)00, a = 5.24700(1) Å, c = 11.45514(3) Å, q1 = 0.51637(14)a* + 0.80761(13)b*, q2 = -0.80761a* + 0.51637b*]. At x = 0.4, the scheelite basic cell undergoes a monoclinic distortion with the formation of the (3 + 1)D structure [superspace group I2/b(a,b,0)00, a = 5.23757(1) Å, b = 5.25035(1) Å, c = 11.45750(2) Å, g = 90.5120(2) o, q = 0.54206(8)a* + 0.79330(8)b*]. In both structures, the antiphase Ca and (Gd,Eu) occupancy modulations indicate that the ordering between the A cations and vacancies also induces partial Ca/(Gd,Eu) cation ordering. Further increase of the Gd3þ content up to x = 0.567 leads to the formation of a monoclinic phase (space group C2/c) with the Eu2/3WO4-type structure. Despite the difference in the cation-vacancy ordering patterns, all materials in the series demonstrate very similar quantum efficiency and luminescence decay lifetimes. However, the difference in the local coordination environment of the A cation species noticeably affects the line width and the multiplet splitting of the 4f6-4f6 transitions. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000397997300045 |
Publication Date |
2017-02-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0925-8388 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.133 |
Times cited |
2 |
Open Access |
OpenAccess |
Notes |
This research was supported by FWO (Flanders Research Foundation, project G039211N). V.A.M. is grateful for financial support of the Russian Foundation for Basic Research (Grant 15-03-07741).We are grateful to the ESRF for granting the beamtime at the ID22 beamline and to Andy Fitch for the support during the experiment. |
Approved |
Most recent IF: 3.133 |
Call Number |
EMAT @ emat @ c:irua:142367 |
Serial |
4581 |
Permanent link to this record |
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Author |
Abakumov, A.M.; Batuk, D.; Tsirlin, A.A.; Prescher, C.; Dubrovinsky, L.; Sheptyakov, D.V.; Schnelle, W.; Hadermann, J.; Van Tendeloo, G. |
Title |
Frustrated pentagonal Cairo lattice in the non-collinear antiferromagnet Bi4Fe5O13F |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
87 |
Issue |
2 |
Pages |
024423-24429 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We report on the crystal structure and magnetism of the iron-based oxyfluoride Bi4Fe5O13F, a material prototype of the Cairo pentagonal spin lattice. The crystal structure of Bi4Fe5O13F is determined by a combination of neutron diffraction, synchrotron x-ray diffraction, and transmission electron microscopy. It comprises layers of FeO6 octahedra and FeO4 tetrahedra forming deformed pentagonal units. The topology of these layers resembles a pentagonal least-perimeter tiling, which is known as the Cairo lattice. This topology gives rise to frustrated exchange couplings and underlies a sequence of magnetic transitions at T-1 = 62 K, T-2 = 71 K, and T-N = 178 K, as determined by thermodynamic measurements and neutron diffraction. Below T-1, Bi4Fe5O13F forms a fully ordered non-collinear antiferromagnetic structure, whereas the magnetic state between T-1 and T-N may be partially disordered according to the sizable increase in the magnetic entropy at T-1 and T-2. Bi4Fe5O13F reveals unanticipated magnetic transitions on the pentagonal Cairo spin lattice and calls for a further work on finite-temperature properties of this strongly frustrated spin model. DOI: 10.1103/PhysRevB.87.024423 |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000314224800002 |
Publication Date |
2013-02-01 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
17 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
Call Number |
UA @ lucian @ c:irua:107688 |
Serial |
1293 |
Permanent link to this record |
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Author |
Zhang, L.; Batuk, D.; Chen, G.; Tarascon, J.-M. |
Title |
Electrochemically activated MnO as a cathode material for sodium-ion batteries |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Electrochemistry communications |
Abbreviated Journal |
Electrochem Commun |
Volume |
77 |
Issue |
|
Pages |
81-84 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Besides classical electrode materials pertaining to Li-ion batteries, recent interest has been devoted to pairs of active redox composites having a redox center and an intercalant source. Taking advantage of the NaPFG salt decomposition above 4.2 V. we extrapolate this concept to the electrochemical in situ preparation of F-based MnO composite electrodes for Na-ion batteries. Such electrodes exhibit a reversible discharge capacity of 145 mAh g(-1) at room temperature. The amorphization of pristine MnO electrode after activation is attributed to the electrochemical grinding effect caused by substantial atomic migration and lattice strain build-up upon cycling. (C) 2017 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000399510400019 |
Publication Date |
2017-02-28 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1388-2481 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.396 |
Times cited |
8 |
Open Access |
OpenAccess |
Notes |
; This work was partially supported by the Hong Kong Research Grants Council under the General Research Fund Project #611213. L.Z. thanks the HKUST for his Postgraduate Studentship. ; |
Approved |
Most recent IF: 4.396 |
Call Number |
UA @ lucian @ c:irua:143648 |
Serial |
4650 |
Permanent link to this record |
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Author |
Batuk, D.; Batuk, M.; Tsirlin, A.A.; Hadermann, J.; Abakumov, A.M. |
Title |
Trapping of Oxygen Vacancies at Crystallographic Shear Planes in Acceptor-Doped Pb-Based Ferroelectrics |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
Volume |
54 |
Issue |
54 |
Pages |
14787-14790 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The defect chemistry of the ferroelectric material PbTiO3 after doping with Fe(III) acceptor ions is reported. Using advanced transmission electron microscopy and powder X-ray and neutron diffraction, we demonstrate that even at concentrations as low as circa 1.7% (material composition approximately ABO2.95), the oxygen vacancies are trapped into extended planar defects, specifically crystallographic shear planes. We investigate the evolution of these defects upon doping and unravel their detailed atomic structure using the formalism of superspace crystallography, thus unveiling their role in nonstoichiometry in the Pb-based perovskites. |
Address |
Chemistry Department, Moscow State University, 119991, Moscow (Russia). artem.abakumov@uantwerpen.be |
Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
English |
Wos |
000367723400031 |
Publication Date |
2015-10-21 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1433-7851 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
11.994 |
Times cited |
3 |
Open Access |
|
Notes |
A.M.A. is grateful to the Russian Science Foundation (grant 14-13-00680). AT was funded by the Mobilitas grant MTT77 of the ESF and by the Federal Ministry for Education and Research through the Sofja Kovalevskaya Award of Alexander von Humboldt Foundation. |
Approved |
Most recent IF: 11.994; 2015 IF: 11.261 |
Call Number |
c:irua:131104 |
Serial |
4080 |
Permanent link to this record |
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Author |
Pearce, P.E.; Perez, A.J.; Rousse, G.; Saubanère, M.; Batuk, D.; Foix, D.; McCalla, E.; Abakumov, A.M.; Van Tendeloo, G.; Doublet, M.-L.; Tarascon, J.-M. |
Title |
Evidence for anionic redox activity in a tridimensional-ordered Li-rich positive electrode β-Li2IrO3 |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Nature materials |
Abbreviated Journal |
Nat Mater |
Volume |
16 |
Issue |
5 |
Pages |
580-586 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Lithium-ion battery cathode materials have relied on cationic redox reactions until the recent discovery of anionic redox activity in Li-rich layered compounds which enables capacities as high as 300 mAh g(-1). In the quest for new high-capacity electrodes with anionic redox, a still unanswered question was remaining regarding the importance of the structural dimensionality. The present manuscript provides an answer. We herein report on a beta-Li2IrO3 phase which, in spite of having the Ir arranged in a tridimensional (3D) framework instead of the typical two-dimensional (2D) layers seen in other Li-rich oxides, can reversibly exchange 2.5 e(-) per Ir, the highest value ever reported for any insertion reaction involving d-metals. We show that such a large activity results from joint reversible cationic (Mn+) and anionic (O-2)(n-) redox processes, the latter being visualized via complementary transmission electron microscopy and neutron diffraction experiments, and confirmed by density functional theory calculations. Moreover, beta-Li2IrO3 presents a good cycling behaviour while showing neither cationic migration nor shearing of atomic layers as seen in 2D-layered Li-rich materials. Remarkably, the anionic redox process occurs jointly with the oxidation of Ir4+ at potentials as low as 3.4 V versus Li+/Li-0, as equivalently observed in the layered alpha-Li2IrO3 polymorph. Theoretical calculations elucidate the electrochemical similarities and differences of the 3D versus 2D polymorphs in terms of structural, electronic and mechanical descriptors. Our findings free the structural dimensionality constraint and broaden the possibilities in designing high-energy-density electrodes for the next generation of Li-ion batteries. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000400004200018 |
Publication Date |
2017-02-27 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1476-1122 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
39.737 |
Times cited |
|
Open Access |
Not_Open_Access |
Notes |
The authors thank Q. Jacquet for fruitful discussions and V. Pomjakushin for his valuable help in neutron diffraction experiments. This work is based on experiments performed at the Swiss Spallation Neutron Source SINQ, Paul Scherrer Institute, Villigen, Switzerland. Use of the 11-BM mail service of the APS at Argonne National Laboratory was supported by the US Department of Energy under contract No. DE-AC02-06CH11357 and is greatly acknowledged. J.-M.T. acknowledges funding from the European Research Council (ERC) (FP/2014)/ERC Grant-Project 670116-ARPEMA. E.M. acknowledges financial support from the Fonds de Recherche du Quebec-Nature et Technologies. |
Approved |
Most recent IF: 39.737 |
Call Number |
EMAT @ emat @c:irua:147502 |
Serial |
4773 |
Permanent link to this record |
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Author |
Erni, R.; Abakumov, A.M.; Rossell, M.D.; Batuk, D.; Tsirlin, A.A.; Nénert, G.; Van Tendeloo, G. |
Title |
Nanoscale phase separation in perovskites revisited |
Type |
L1 Letter to the editor |
Year |
2014 |
Publication |
Nature materials |
Abbreviated Journal |
Nat Mater |
Volume |
13 |
Issue |
3 |
Pages |
216-217 |
Keywords |
L1 Letter to the editor; Electron microscopy for materials research (EMAT) |
Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000331945200002 |
Publication Date |
2014-02-20 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1476-1122;1476-4660; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
39.737 |
Times cited |
5 |
Open Access |
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Notes |
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Approved |
Most recent IF: 39.737; 2014 IF: 36.503 |
Call Number |
UA @ lucian @ c:irua:114579 |
Serial |
2270 |
Permanent link to this record |
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Author |
Tyablikov, O.A.; Batuk, D.; Tsirlin, A.A.; Batuk, M.; Verchenko, V.Y.; Filimonov, D.S.; Pokholok, K.V.; Sheptyakov, D.V.; Rozova, M.G.; Hadermann, J.; Antipov, E.V.; Abakumov, A.M.; |
Title |
{110}-Layered B-cation ordering in the anion-deficient perovskite Pb2.4Ba2.6Fe2Sc2TiO13 with the crystallographic shear structure |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
Dalton T |
Volume |
44 |
Issue |
44 |
Pages |
10753-10762 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A novel anion-deficient perovskite-based compound, Pb2.4Ba2.6Fe2Sc2TiO13, was synthesized via the citrate-based route. This compound is an n = 5 member of the A(n)B(n)O(3n-2) homologous series with unit-cell parameters related to the perovskite subcell a(p) approximate to 4.0 angstrom as a(p)root 2 x a(p) x 5a(p)root 2. The crystal structure of Pb2.4Ba2.6Fe2Sc2TiO13 consists of quasi-2D perovskite blocks with a thickness of three octahedral layers separated by the 1/2[110]((1) over bar 01)(p) crystallographic shear (CS) planes, which are parallel to the {110} plane of the perovskite subcell. The CS planes transform the corner-sharing octahedra into chains of edge-sharing distorted tetragonal pyramids. Using a combination of neutron powder diffraction, Fe-57 Mossbauer spectroscopy and atomic resolution electron energy-loss spectroscopy we demonstrate that the B-cations in Pb2.4Ba2.6Fe2Sc2TiO13 are ordered along the {110} perovskite layers with Fe3+ in distorted tetragonal pyramids along the CS planes, Ti4+ preferentially in the central octahedra of the perovskite blocks and Sc3+ in the outer octahedra of the perovskite blocks. Magnetic susceptibility and Mossbauer spectroscopy indicate a broadened magnetic transition around T-N similar to 45 K and the onset of local magnetic fields at low temperatures. The magnetic order is probably reminiscent of that in other A(n)B(n)O(3n-2) homologues, where G-type AFM order within the perovskite blocks has been observed. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000355701000026 |
Publication Date |
2015-01-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1477-9226;1477-9234; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.029 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.029; 2015 IF: 4.197 |
Call Number |
c:irua:127001 |
Serial |
22 |
Permanent link to this record |
|
|
|
Author |
Lutz, L.; Corte, D.A.D.; Chen, Y.; Batuk, D.; Johnson, L.R.; Abakumov, A.; Yate, L.; Azaceta, E.; Bruce, P.G.; Tarascon, J.-M.; Grimaud, A. |
Title |
The role of the electrode surface in Na-Air batteries : insights in electrochemical product formation and chemical growth of NaO2 |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Advanced energy materials |
Abbreviated Journal |
Adv Energy Mater |
Volume |
8 |
Issue |
4 |
Pages |
1701581 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The Na-air battery, because of its high energy density and low charging overpotential, is a promising candidate for low-cost energy storage, hence leading to intensive research. However, to achieve such a battery, the role of the positive electrode material in the discharge process must be understood. This issue is herein addressed by exploring the electrochemical reduction of oxygen, as well as the chemical formation and precipitation of NaO2 using different electrodes. Whereas a minor influence of the electrode surface is demonstrated on the electrochemical formation of NaO2, a strong dependence of the subsequent chemical precipitation of NaO2 is identified. In the origin, this effect stems from the surface energy and O-2/O-2(-) affinity of the electrode. The strong interaction of Au with O-2/O-2(-) increases the nucleation rate and leads to an altered growth process when compared to C surfaces. Consequently, thin (3 mu m) flakes of NaO2 are found on Au, whereas on C large cubes (10 mu m) of NaO2 are formed. This has significant impact on the cell performance and leads to four times higher capacity when C electrodes with low surface energy and O-2/O-2(-) affinity are used. It is hoped that these findings will enable the design of new positive electrode materials with optimized surfaces. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
WILEY-VCH Verlag GmbH & Co. |
Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
000424152200009 |
Publication Date |
2017-09-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1614-6832; 1614-6840 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
16.721 |
Times cited |
13 |
Open Access |
Not_Open_Access |
Notes |
; L.L. thanks ALISTORE-ERI for his PhD grant. P.G.B. is indebted to the EPSRC for financial support, including the Supergen Energy Storage grant. ; |
Approved |
Most recent IF: 16.721 |
Call Number |
UA @ lucian @ c:irua:149269 |
Serial |
4951 |
Permanent link to this record |
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|
|
Author |
Gonnissen, J.; Batuk, D.; Nataf, G.F.; Jones, L.; Abakumov, A.M.; Van Aert, S.; Schryvers, D.; Salje, E.K.H. |
Title |
Direct Observation of Ferroelectric Domain Walls in LiNbO3: Wall-Meanders, Kinks, and Local Electric Charges |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
Volume |
26 |
Issue |
26 |
Pages |
7599-7604 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Direct observations of the ferroelectric domain boundaries in LiNbO3 are performed using high-resolution high-angle annular dark field scanning transmission electron microscopy imaging, revealing a very narrow width of the domain wall between the 180° domains. The domain walls demonstrate local side-way meandering, which results in inclinations even when the overall wall orientation follows the ferroelectric polarization. These local meanders contain kinks with “head-to-head” and “tail-to-tail” dipolar configurations and are therefore locally charged. The charged meanders are confined to a few cation layers along the polarization direction and are separated by longer stretches of straight domain walls. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000388166700006 |
Publication Date |
2016-09-16 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1616-301X |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
23 |
Open Access |
|
Notes |
J.G. acknowledges the support from the Research Foundation Flanders (FWO, Belgium) through various project fundings (G.0368.15N, G.0369.15N, and G.0374.13N), as well as the financial support from the European Union Seventh Framework Program (FP7/2007–2013) under Grant agreement no. 312483 (ESTEEM2). The authors thank J. Hadermann for useful suggestions on the interpretation of the HAADFSTEM images. E.K.H.S. thanks the EPSRC (EP/K009702/1) and the Leverhulme Trust (EM-2016-004) for support. G.F.N. thanks the National Research Fund, Luxembourg (FNR/P12/4853155/Kreisel) for support.; esteem2_jra2 |
Approved |
Most recent IF: 12.124 |
Call Number |
c:irua:135336 c:irua:135336 |
Serial |
4129 |
Permanent link to this record |
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|
|
Author |
Li, D.Y.; Zeng, Y.J.; Batuk, D.; Pereira, L.M.C.; Ye, Z.Z.; Fleischmann, C.; Menghini, M.; Nikitenko, S.; Hadermann, J.; Temst, K.; Vantomme, A.; Van Bael, M.J.; Locquet, J.P.; Van Haesendonck, C.; |
Title |
Relaxor ferroelectricity and magnetoelectric coupling in ZnOCo nanocomposite thin films : beyond multiferroic composites |
Type |
A1 Journal article |
Year |
2014 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
6 |
Issue |
7 |
Pages |
4737-4742 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
ZnOCo nanocomposite thin films are synthesized by combination of pulsed laser deposition of ZnO and Co ion implantation. Both superparamagnetism and relaxor ferroelectricity as well as magnetoelectric coupling in the nanocomposites have been demonstrated. The unexpected relaxor ferroelectricity is believed to be the result of the local lattice distortion induced by the incorporation of the Co nanoparticles. Magnetoelectric coupling can be attributed to the interaction between the electric dipole moments and the magnetic moments, which are both induced by the incorporation of Co. The introduced ZnOCo nanocomposite thin films are different from conventional strain-mediated multiferroic composites. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000334572800018 |
Publication Date |
2014-03-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1944-8244;1944-8252; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.504 |
Times cited |
21 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 7.504; 2014 IF: 6.723 |
Call Number |
UA @ lucian @ c:irua:117063 |
Serial |
2864 |
Permanent link to this record |
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|
|
Author |
Yang, C.; Laberty-Robert, C.; Batuk, D.; Cibin, G.; Chadwick, A.V.; Pimenta, V.; Yin, W.; Zhang, L.; Tarascon, J.-M.; Grimaud, A. |
Title |
Phosphate ion functionalization of perovskite surfaces for enhanced oxygen evolution reaction |
Type |
A1 Journal article |
Year |
2017 |
Publication |
The journal of physical chemistry letters |
Abbreviated Journal |
J Phys Chem Lett |
Volume |
8 |
Issue |
15 |
Pages |
3466-3472 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Recent findings revealed that surface oxygen can participate in the oxygen evolution reaction (OER) for the most active catalysts, which eventually triggers a new mechanism for which the deprotonation of surface intermediates limits the OER activity. We propose in this work a “dual strategy” in which tuning the electronic properties of the oxide, such as La1-xSrxCoO3-delta, can be dissociated from the use of surface functionalization with phosphate ion groups (P-i) that enhances the interfacial proton transfer. Results show that the P-i functionalized La0.5Sr0.5CoO3-delta gives rise to a significant enhancement of the OER activity when compared to La0.5Sr0.5Co3-delta and LaCoO3. We further demonstrate that the P-i surface functionalization selectivity enhances the activity when the OER kinetics is limited by the proton transfer. Finally, this work suggests that tuning the catalytic activity by such a “dual approach” may be a new and largely unexplored avenue for the design of novel high-performance catalysts. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Chemical Society |
Place of Publication |
Washington, D.C |
Editor |
|
Language |
|
Wos |
000407191300003 |
Publication Date |
2017-07-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1948-7185 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.353 |
Times cited |
31 |
Open Access |
OpenAccess |
Notes |
; C.Y., J.-M.T., D.B., and A.G. acknowledge funding from the European Research Council (ERC) (FP/2014)/ERC Grant-Project 670116-ARPEMA. We acknowledge Diamond Light Source for time awarded to the Energy Materials BAG on Beamline B18, under Proposal sp12559. ; |
Approved |
Most recent IF: 9.353 |
Call Number |
UA @ lucian @ c:irua:145730 |
Serial |
4747 |
Permanent link to this record |
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|
|
Author |
Guzzinati, G.; Altantzis, T.; Batuk, M.; De Backer, A.; Lumbeeck, G.; Samaee, V.; Batuk, D.; Idrissi, H.; Hadermann, J.; Van Aert, S.; Schryvers, D.; Verbeeck, J.; Bals, S. |
Title |
Recent Advances in Transmission Electron Microscopy for Materials Science at the EMAT Lab of the University of Antwerp |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Materials |
Abbreviated Journal |
Materials |
Volume |
11 |
Issue |
11 |
Pages |
1304 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The rapid progress in materials science that enables the design of materials down to the nanoscale also demands characterization techniques able to analyze the materials down to the same scale, such as transmission electron microscopy. As Belgium’s foremost electron microscopy group, among the largest in the world, EMAT is continuously contributing to the development of TEM techniques, such as high-resolution imaging, diffraction, electron tomography, and spectroscopies, with an emphasis on quantification and reproducibility, as well as employing TEM methodology at the highest level to solve real-world materials science problems. The lab’s recent contributions are presented here together with specific case studies in order to highlight the usefulness of TEM to the advancement of materials science. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000444112800041 |
Publication Date |
2018-07-28 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1996-1944 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.654 |
Times cited |
15 |
Open Access |
OpenAccess |
Notes |
Fonds Wetenschappelijk Onderzoek, G.0502.18N, G.0267.18N, G.0120.12N, G.0365.15N, G.0934.17N, S.0100.18N AUHA13009 ; European Research Council, COLOURATOM 335078 ; Universiteit Antwerpen, GOA Solarpaint ; G. Guzzinati, T. Altantzis and A. De Backer have been supported by postdoctoral fellowship grants from the Research Foundation Flanders (FWO). Funding was also received from the European Research Council (starting grant no. COLOURATOM 335078), the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 770887), the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0502.18N, G.0267.18N, G.0120.12N, G.0365.15N, G.0934.17N, S.0100.18N, G.0401.16N) and from the University of Antwerp through GOA project Solarpaint. Funding for the TopSPIN precession system under grant AUHA13009, as well as for the Qu-Ant-EM microscope, is acknowledged from the HERCULES Foundation. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (F.R.S.-FNRS). (ROMEO:green; preprint:; postprint:can ; pdfversion:can); saraecas; ECAS_Sara; |
Approved |
Most recent IF: 2.654 |
Call Number |
EMAT @ emat @c:irua:153737UA @ admin @ c:irua:153737 |
Serial |
5064 |
Permanent link to this record |
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|
|
Author |
Batuk, D.; Batuk, M.; Abakumov, A.M.; Hadermann, J. |
Title |
Synergy between transmission electron microscopy and powder diffraction : application to modulated structures |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Acta crystallographica: section B: structural science |
Abbreviated Journal |
Acta Crystallogr B |
Volume |
71 |
Issue |
71 |
Pages |
127-143 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The crystal structure solution of modulated compounds is often very challenging, even using the well established methodology of single-crystal X-ray crystallography. This task becomes even more difficult for materials that cannot be prepared in a single-crystal form, so that only polycrystalline powders are available. This paper illustrates that the combined application of transmission electron microscopy (TEM) and powder diffraction is a possible solution to the problem. Using examples of anion-deficient perovskites modulated by periodic crystallographic shear planes, it is demonstrated what kind of local structural information can be obtained using various TEM techniques and how this information can be implemented in the crystal structure refinement against the powder diffraction data. The following TEM methods are discussed: electron diffraction (selected area electron diffraction, precession electron diffraction), imaging (conventional high-resolution TEM imaging, high-angle annular dark-field and annular bright-field scanning transmission electron microscopy) and state-of-the-art spectroscopic techniques (atomic resolution mapping using energy-dispersive X-ray analysis and electron energy loss spectroscopy). |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Copenhagen |
Editor |
|
Language |
|
Wos |
000352166500002 |
Publication Date |
2015-04-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
2052-5206; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.032 |
Times cited |
11 |
Open Access |
|
Notes |
Fwo G039211n |
Approved |
Most recent IF: 2.032; 2015 IF: NA |
Call Number |
c:irua:124411 |
Serial |
3408 |
Permanent link to this record |
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|
|
Author |
Perez, A.J.; Jacquet, Q.; Batuk, D.; Iadecola, A.; Saubanere, M.; Rousse, G.; Larcher, D.; Vezin, H.; Doublet, M.-L.; Tarascon, J.-M. |
Title |
Approaching the limits of cationic and anionic electrochemical activity with the Li-rich layered rocksalt Li3IrO4 |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Nature energy |
Abbreviated Journal |
Nat Energy |
Volume |
2 |
Issue |
12 |
Pages |
954-962 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The Li-rich rocksalt oxides Li2MO3 (M = 3d/4d/5d transition metal) are promising positive-electrode materials for Li-ion batteries, displaying capacities exceeding 300 mAh g(-1) thanks to the participation of the oxygen non-bonding O(2p) orbitals in the redox process. Understanding the oxygen redox limitations and the role of the O/M ratio is therefore crucial for the rational design of materials with improved electrochemical performances. Here we push oxygen redox to its limits with the discovery of a Li3IrO4 compound (O/M = 4) that can reversibly take up and release 3.5 electrons per Ir and possesses the highest capacity ever reported for any positive insertion electrode. By quantitatively monitoring the oxidation process, we demonstrate the material's instability against O-2 release on removal of all Li. Our results show that the O/M parameter delineates the boundary between the material's maximum capacity and its stability, hence providing valuable insights for further development of high-capacity materials. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000430218300001 |
Publication Date |
2017-12-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
2058-7546 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
55 |
Open Access |
Not_Open_Access |
Notes |
; We thank P. Pearce for providing the beta-Li<INF>2</INF>IrO<INF>3</INF> and L. Lemarquis for helping in the DEMS experiment. We are particularly grateful to S. Belin, V. Briois and L. Stievano for helpful discussions on XAS analysis and synchrotron SOLEIL (France) for providing beamtime at the ROCK beamline (financed by the French National Research Agency (ANR) as part of the 'Investissements d'Avenir' programme, reference: ANR-10-EQPX-45). A.J.P and A. I. acknowledge the GdR C(RS) 2 for the workshop organized on a chemometric approach for XAS data analysis. V. Nassif is acknowledged for her help during neutron diffraction experiments performed at Institut Laue Langevin on D1B. Use of the 11-BM mail service of the APS at Argonne National Laboratory was supported by the US Department of Energy under contract No. DE-AC02-06CH11357 and is gratefully acknowledged. This work has been performed with the support of the European Research Council (ERC) (FP/2014)/ERC Grant- Project 670116 ARPEMA. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:150926 |
Serial |
4962 |
Permanent link to this record |
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|
Author |
Zhang, B.; Deschamps, M.; Ammar, M.-R.; Raymundo-Pinero, E.; Hennet, L.; Batuk, D.; Tarascon, J.-M. |
Title |
Laser synthesis of hard carbon for anodes in Na-ion battery |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Advanced Materials Technologies |
Abbreviated Journal |
|
Volume |
2 |
Issue |
3 |
Pages |
1600227 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000398999900003 |
Publication Date |
2016-12-19 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
2365-709x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
10 |
Open Access |
Not_Open_Access |
Notes |
; The RS2E (Reseau sur le StockageElectrochimique de l'Energie) network is acknowledged for the financial support of this work through the ANR project Storex (ANR-10-LABX-76-01). J.-M.T acknowledges funding from the European Research Council (ERC) (FP/2014-2020)/ERC GrantProject 670116-ARPEMA. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:142452 |
Serial |
4666 |
Permanent link to this record |
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|
|
Author |
Tsirlin, A.A.; Rousochatzakis, I.; Filimonov, D.; Batuk, D.; Frontzek, M.; Abakumov, A.M. |
Title |
Spin-reorientation transitions in the Cairo pentagonal magnet Bi4Fe5O13F |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
96 |
Issue |
9 |
Pages |
094420 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We show that interlayer spins play a dual role in the Cairo pentagonal magnet Bi4Fe5O13F, on one hand mediating the three-dimensional magnetic order, and on the other driving spin-reorientation transitions both within and between the planes. The corresponding sequence of magnetic orders unraveled by neutron diffraction and Mossbauer spectroscopy features two orthogonal magnetic structures described by opposite local vector chiralities, and an intermediate, partly disordered phase with nearly collinear spins. A similar collinear phase has been predicted theoretically to be stabilized by quantum fluctuations, but Bi4Fe5O13F is very far from the relevant parameter regime. While the observed in-plane reorientation cannot be explained by any standard frustration mechanism, our ab initio band-structure calculations reveal strong single-ion anisotropy of the interlayer Fe3+ spins that turns out to be instrumental in controlling the local vector chirality and the associated interlayer order. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000411161700002 |
Publication Date |
2017-09-19 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
7 |
Open Access |
OpenAccess |
Notes |
We are grateful to J.-M. Perez-Mato and Dmitry Khalyavin for valuable discussions on the magnetic structures and symmetries. D.F. and A.A. are grateful to the Russian Science Foundation (Grant No. 14-13-00680) for support. A.T. was supported by the Federal Ministry for Education and Research through the Sofja Kovalevskaya Award of the Alexander von Humboldt Foundation. This work is based on experiments performed at the Swiss spallation neutron source SINQ, Paul Scherrer Institut, Villigen, Switzerland. |
Approved |
Most recent IF: 3.836 |
Call Number |
EMAT @ emat @c:irua:146748 |
Serial |
4774 |
Permanent link to this record |
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|
|
Author |
Takatsu, H.; Hernandez, O.; Yoshimune, W.; Prestipino, C.; Yamamoto, T.; Tassel, C.; Kobayashi, Y.; Batuk, D.; Shibata, Y.; Abakumov, A.M.; Brown, C.M.; Kageyama, H. |
Title |
Cubic lead perovskite PbMoO3 with anomalous metallic behavior |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Physical review B |
Abbreviated Journal |
|
Volume |
95 |
Issue |
15 |
Pages |
155105 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A previously unreported Pb-based perovskite PbMoO3 is obtained by high-pressure and high-temperature synthesis. This material crystallizes in the Pm3m cubic structure at room temperature, making it distinct from typical Pb-based perovskite oxides with a structural distortion. PbMoO3 exhibits a metallic behavior down to 0.1 K with an unusual T-sublinear dependence of the electrical resistivity. Moreover, a large specific heat is observed at low temperatures accompanied by a peak in C-P/T-3 around 10 K, in marked contrast to the isostructural metallic system SrMoO3. These transport and thermal properties for PbMoO3, taking into account anomalously large Pb atomic displacements detected through diffraction experiments, are attributed to a low-energy vibrational mode, associated with incoherent off-centering of lone-pair Pb2+ cations. We discuss the unusual behavior of the electrical resistivity in terms of a polaronlike conduction, mediated by the strong coupling between conduction electrons and optical phonons of the local low-energy vibrational mode. |
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000440605700001 |
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2017-04-04 |
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2469-9969; 2469-9950 |
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UA library record; WoS full record; WoS citing articles |
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UA @ admin @ c:irua:167288 |
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7743 |
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