Records |
Author |
Chen, Y.Z.; Trier, F.; Wijnands, T.; Green, R.J.; Gauquelin, N.; Egoavil, R.; Christensen, D.V.; Koster, G.; Huijben, M.; Bovet, N.; Macke, S.; He, F.; Sutarto, R.; Andersen, N.H.; Sulpizio, J.A.; Honig, M.; Prawiroatmodjo, G.E.D.K.; Jespersen, T.S.; Linderoth, S.; Ilani, S.; Verbeeck, J.; Van Tendeloo, G.; Rijnders, G.; Sawatzky, G.A.; Pryds, N. |
Title |
Extreme mobility enhancement of two-dimensional electron gases at oxide interfaces by charge-transfer-induced modulation doping |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nature materials |
Abbreviated Journal |
Nat Mater |
Volume |
14 |
Issue |
14 |
Pages |
801-806 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Two-dimensional electron gases (2DEGs) formed at the interface of insulating complex oxides promise the development of all-oxide electronic devices. These 2DEGs involve many-body interactions that give rise to a variety of physical phenomena such as superconductivity, magnetism, tunable metalinsulator transitions and phase separation. Increasing the mobility of the 2DEG, however, remains a major challenge. Here, we show that the electron mobility is enhanced by more than two orders of magnitude by inserting a single-unit-cell insulating layer of polar La1−xSrxMnO3 (x = 0, 1/8, and 1/3) at the interface between disordered LaAlO3 and crystalline SrTiO3 produced at room temperature. Resonant X-ray spectroscopy and transmission electron microscopy show that the manganite layer undergoes unambiguous electronic reconstruction, leading to modulation doping of such atomically engineered complex oxide heterointerfaces. At low temperatures, the modulation-doped 2DEG exhibits Shubnikovde Haas oscillations and fingerprints of the quantum Hall effect, demonstrating unprecedented high mobility and low electron density. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000358530100022 |
Publication Date |
2015-06-01 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1476-1122;1476-4660; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
39.737 |
Times cited |
170 |
Open Access |
|
Notes |
246102 IFOX; 246791 COUNTATOMS; 278510 VORTEX; Hercules; 312483 ESTEEM2; FWO G004413N; esteem2jra3 ECASJO; |
Approved |
Most recent IF: 39.737; 2015 IF: 36.503 |
Call Number |
c:irua:127184 c:irua:127184UA @ admin @ c:irua:127184 |
Serial |
1163 |
Permanent link to this record |
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Author |
Navulla, A.; Tsirlin, A.A.; Abakumov, A.M.; Shpanchenko, R.V.; Zhang, H.; Dikarev, E.V. |
Title |
Fluorinated heterometallic \beta-diketonates as volatile single-source precursors for the synthesis of low-valent mixed-metal fluorides |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
Volume |
133 |
Issue |
4 |
Pages |
692-694 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Hexafluoroacetylacetonates that contain lead and divalent first-row transition metals, PbM(hfac)4 (M = Ni (1), Co (2), Mn (3), Fe (4), and Zn (5)), have been synthesized. Their heterometallic structures are held together by strong Lewis acid−base interactions between metal atoms and diketonate ligands acting in chelating−bridging fashion. Compounds 1−5 are highly volatile and decompose below 350 °C. Fluorinated heterometallic β-diketonates have been used for the first time as volatile single-source precursors for the preparation of mixed-metal fluorides. Complex fluorides of composition Pb2MF6 have been obtained by decomposition of 1−5 in a two-zone furnace under low-pressure nitrogen flow. Lead−transition metal fluorides conform to orthorhombically distorted Aurivillius-type structure with layers of corner-sharing [MF6] octahedra separated by α-PbO-type (Pb2F2) blocks. Pb2NiF6 and Pb2CoF6 were found to exhibit magnetic ordering below 80 and 43 K, respectively. The ordering is antiferromagnetic, with a weak, uncompensated moment due to the canting of spins. The Pb2MF6 fluorides represent a new class of prospective magnetoelectric materials combining transition metals and lone-pair main-group cations. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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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 |
000287295300015 |
Publication Date |
2010-12-21 |
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 |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.858 |
Times cited |
28 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 13.858; 2011 IF: 9.907 |
Call Number |
UA @ lucian @ c:irua:88820 |
Serial |
1236 |
Permanent link to this record |
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Author |
Xu, B.; Milošević, M.V.; Lin, S.-H.; Peeters, F.M.; Jankó, B. |
Title |
Formation of multiple-flux-quantum vortices in mesoscopic superconductors from simulations of calorimetric, magnetic, and transport properties |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
Volume |
107 |
Issue |
5 |
Pages |
057002,1-057002,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Because of strong flux confinement in mesoscopic superconductors, a giant vortex may appear in the ground state of the system in an applied magnetic field. This multiquanta vortex can then split into individual vortices (and vice versa) as a function of, e.g., applied current, magnetic field, or temperature. Here we show that such transitions can be identified by calorimetry, as the formation or splitting of a giant vortex results in a clear jump in measured heat capacity versus external drive. We attribute this phenomenon to an abrupt change in the density of states of the quasiparticle excitations in the vortex core(s), and further link it to a sharp change of the magnetic susceptibility at the transitionproving that the formation of a giant vortex can also be detected by magnetometry. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000293333100006 |
Publication Date |
2011-07-29 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.462 |
Times cited |
26 |
Open Access |
|
Notes |
; We thank O. Bourgeois, T. Yokoyama, M. Eschrig, and M. Ichioka for discussions. This work was supported by FWO-Vlaanderen, the Belgian Science Policy (IAP), the bilateral project Flanders-USA, NSF NIRT, ECS-0609249, and Institute of Theoretical Sciences, Notre Dame. ; |
Approved |
Most recent IF: 8.462; 2011 IF: 7.370 |
Call Number |
UA @ lucian @ c:irua:91237 |
Serial |
1263 |
Permanent link to this record |
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Author |
Abakumov, A.M.; Erni, R.; Tsirlin, A.A.; Rossell, M.D.; Batuk, D.; Nénert, G.; Van Tendeloo, G. |
Title |
Frustrated octahedral tilting distortion in the incommensurately modulated Li3xNd2/3-xTiO3 perovskites |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
25 |
Issue |
13 |
Pages |
2670-2683 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Perovskite-structured titanates with layered A-site ordering form remarkably complex superstructures. Using transmission electron microscopy, synchrotron X-ray and neutron powder diffraction, and ab initio structure relaxation, we present the structural solution of the incommensurately modulated Li3xNd2/3xTiO3 perovskites (x = 0.05, superspace group Pmmm(α1,1/2,0)000(1/2,β2 0)000, a = 3.831048(5) Å, b = 3.827977(4) Å, c = 7.724356(8) Å, q1 = 0.45131(8)a* + 1/2b*, q2 = 1/2a* + 0.41923(4)b*). In contrast to earlier conjectures on the nanoscale compositional phase separation in these materials, all peculiarities of the superstructure can be understood in terms of displacive modulations related to an intricate octahedral tilting pattern. It involves fragmenting the pattern of the out-of-phase tilted TiO6 octahedra around the a- and b-axes into antiphase domains, superimposed on the pattern of domains with either pronounced or suppressed in-phase tilt component around the c-axis. The octahedral tilting competes with the second order JahnTeller distortion of the TiO6 octahedra. This competition is considered as the primary driving force for the modulated structure. The A cations are suspected to play a role in this modulation affecting it mainly through the tolerance factor and the size variance. The reported crystal structure calls for a revision of the structure models proposed for the family of layered A-site ordered perovskites exhibiting a similar type of modulated structure. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000321809700015 |
Publication Date |
2013-06-04 |
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 |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
23 |
Open Access |
|
Notes |
Countatoms |
Approved |
Most recent IF: 9.466; 2013 IF: 8.535 |
Call Number |
UA @ lucian @ c:irua:109216 |
Serial |
1292 |
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 ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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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 |
|
Series Issue |
|
Edition |
|
ISSN |
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 |
Tsirlin, A.A.; Nath, R.; Abakumov, A.M.; Shpanchenko, R.V.; Geibel, C.; Rosner, H. |
Title |
Frustrated square lattice with spatial anisotropy: crystal structure and magnetic properties of PbZnVO(PO4)2 |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
81 |
Issue |
17 |
Pages |
174424,1-174424,13 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Crystal structure and magnetic properties of the layered vanadium phosphate PbZnVO(PO4)2 are studied using x-ray powder diffraction, magnetization and specific-heat measurements, as well as band-structure calculations. The compound resembles AA′VO(PO4)2 vanadium phosphates and fits to the extended frustrated square-lattice model with the couplings J1, J1′ between nearest neighbors and J2, J2′ between next-nearest neighbors. The temperature dependence of the magnetization yields estimates of averaged nearest-neighbor and next-nearest-neighbor couplings, J̅ 1≃−5.2 K and J̅ 2≃10.0 K, respectively. The effective frustration ratio α=J̅ 2/J̅ 1 amounts to −1.9 and suggests columnar antiferromagnetic ordering in PbZnVO(PO4)2. Specific-heat data support the estimates of J̅ 1 and J̅ 2 and indicate a likely magnetic ordering transition at 3.9 K. However, the averaged couplings underestimate the saturation field, thus pointing to the spatial anisotropy of the nearest-neighbor interactions. Band-structure calculations confirm the identification of ferromagnetic J1, J1′ and antiferromagnetic J2, J2′ in PbZnVO(PO4)2 and yield (J1′−J1)≃1.1 K in excellent agreement with the experimental value of 1.1 K, deduced from the difference between the expected and experimentally measured saturation fields. Based on the comparison of layered vanadium phosphates with different metal cations, we show that a moderate spatial anisotropy of the frustrated square lattice has minor influence on the thermodynamic properties of the model. We discuss relevant geometrical parameters, controlling the exchange interactions in these compounds and propose a strategy for further design of strongly frustrated square-lattice materials. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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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 |
000278141600082 |
Publication Date |
2010-05-25 |
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 |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
27 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:83384 |
Serial |
1294 |
Permanent link to this record |
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Author |
Lueangchaichaweng, W.; Brooks, N.R.; Fiorilli, S.; Gobechiya, E.; Lin, K.; Li, L.; Parres-Esclapez, S.; Javon, E.; Bals, S.; Van Tendeloo, G.; Martens, J.A.; Kirschhock, C.E.A.; Jacobs, P.A.; Pescarmona, P.P.; |
Title |
Gallium oxide nanorods : novel, template-free synthesis and high catalytic activity in epoxidation reactions |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
Volume |
53 |
Issue |
6 |
Pages |
1585-1589 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Gallium oxide nanorods with unprecedented small dimensions (20-80nm length and 3-5nm width) were prepared using a novel, template-free synthesis method. This nanomaterial is an excellent heterogeneous catalyst for the sustainable epoxidation of alkenes with H2O2, rivaling the industrial benchmark microporous titanosilicate TS-1 with linear alkenes and being much superior with bulkier substrates. A thorough characterization study elucidated the correlation between the physicochemical properties of the gallium oxide nanorods and their catalytic performance, and underlined the importance of the nanorod morphology for generating a material with high specific surface area and a high number of accessible acid sites. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
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Language |
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Wos |
000330558400021 |
Publication Date |
2014-01-22 |
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 |
|
ISSN |
1433-7851; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
11.994 |
Times cited |
61 |
Open Access |
OpenAccess |
Notes |
START 1; Methusalem; Prodex; IAP-PAI; and the ERC (grant number 24691-COUNTATOMS and grant number 335078-COLOURATOM) projects; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); |
Approved |
Most recent IF: 11.994; 2014 IF: 11.261 |
Call Number |
UA @ lucian @ c:irua:115726 |
Serial |
1314 |
Permanent link to this record |
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Author |
Ovsyannikov, S.V.; Karkin, A.E.; Morozova, N.V.; Shchennikov, V.V.; Bykova, E.; Abakumov, A.M.; Tsirlin, A.A.; Glazyrin, K.V.; Dubrovinsky, L. |
Title |
A hard oxide semiconductor with a direct and narrow bandgap and switchable pn electrical conduction |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
Volume |
26 |
Issue |
48 |
Pages |
8185-8191 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
An oxide semiconductor (perovskite-type Mn2O3) is reported which has a narrow and direct bandgap of 0.45 eV and a high Vickers hardness of 15 GPa. All the known materials with similar electronic band structures (e.g., InSb, PbTe, PbSe, PbS, and InAs) play crucial roles in the semiconductor industry. The perovskite-type Mn2O3 described is much stronger than the above semiconductors and may find useful applications in different semiconductor devices, e.g., in IR detectors. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
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Language |
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Wos |
000346480800016 |
Publication Date |
2014-10-27 |
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 |
|
ISSN |
0935-9648; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
19.791 |
Times cited |
27 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 19.791; 2014 IF: 17.493 |
Call Number |
UA @ lucian @ c:irua:122230 |
Serial |
1408 |
Permanent link to this record |
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Author |
King, G.; Abakumov, A.M.; Woodward, P.M.; Llobet, A.; Tsirlin, A.A.; Batuk, D.; Antipov, E.V. |
Title |
The high-temperature polymorphs of K3AlF6 |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
Volume |
50 |
Issue |
16 |
Pages |
7792-7801 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The crystal structures of the three high-temperature polymorphs of K3AlF6 have been solved from neutron powder diffraction, synchrotron X-ray powder diffraction, and electron diffraction data. The β-phase (stable between 132 and 153 °C) and γ-phase (stable between 153 to 306 °C) can be described as unusually complex superstructures of the double-perovskite structure (K2KAlF6) which result from noncooperative tilting of the AlF6 octahedra. The β-phase is tetragonal, space group I4/m, with lattice parameters of a = 13.3862(5) Å and c = 8.5617(3) Å (at 143 °C) and Z = 10. In this phase, one-fifth of the AlF6 octahedra are rotated about the c-axis by 45° while the other four-fifths remain untilted. The large 45° rotations result in edge sharing between these AlF6 octahedra and the neighboring K-centered polyhedra, resulting in pentagonal bipyramidal coordination for four-fifths of the K+ ions that reside on the B-sites of the perovskite structure. The remaining one-fifth of the K+ ions on the B-sites retain octahedral coordination. The γ-phase is orthorhombic, space group Fddd, with lattice parameters of a = 36.1276(4) Å, b = 17.1133(2) Å, and c = 12.0562(1) Å (at 225 °C) and Z = 48. In the γ-phase, one-sixth of the AlF6 octahedra are randomly rotated about one of two directions by 45° while the other five-sixths remain essentially untilted. These rotations result in two-thirds of the K+ ions on the B-site obtaining 7-fold coordination while the other one-third remain in octahedral coordination. The δ-phase adopts the ideal cubic double-perovskite structure, space group Fmm, with a = 8.5943(1) Å at 400 °C. However, pair distribution function analysis shows that locally the δ-phase is quite different from its long-range average crystal structure. The AlF6 octahedra undergo large-amplitude rotations which are accompanied by off-center displacements of the K+ ions that occupy the 12-coordinate A-sites. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
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Place of Publication |
Easton, Pa |
Editor |
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Language |
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Wos |
000293493100052 |
Publication Date |
2011-07-11 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.857 |
Times cited |
19 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.857; 2011 IF: 4.601 |
Call Number |
UA @ lucian @ c:irua:91131 |
Serial |
1468 |
Permanent link to this record |
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Author |
Batuk, M.; Batuk, D.; Tsirlin, A.A.; Rozova, M.G.; Antipov, E.V.; Hadermann, J.; Van Tendeloo, G. |
Title |
Homologous series of layered perovskites An+1BnO3n-1Cl : crystal and magnetic structure of a new oxychloride Pb4BiFe4O11Cl |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
Volume |
52 |
Issue |
4 |
Pages |
2208-2218 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The nuclear and magnetic structure of a novel oxychloride Pb4BiFe4O11Cl has been studied over the temperature range 1.5700 K using a combination of transmission electron microscopy and synchrotron and neutron powder diffraction [space group P4/mbm, a = 5.5311(1) Å, c = 19.586(1) Å, T = 300 K]. Pb4BiFe4O11Cl is built of truncated (Pb,Bi)3Fe4O11 quadruple perovskite blocks separated by CsCl-type (Pb,Bi)2Cl slabs. The perovskite blocks consist of two layers of FeO6 octahedra located between two layers of FeO5 tetragonal pyramids. The FeO6 octahedra rotate about the c axis, resulting in a √2ap × √2ap × c superstructure. Below TN = 595(17) K, Pb4BiFe4O11Cl adopts a G-type antiferromagnetic structure with the iron magnetic moments confined to the ab plane. The ordered magnetic moments at 1.5 K are 3.93(3) and 3.62(4) μB on the octahedral and square-pyramidal iron sites, respectively. Pb4BiFe4O11Cl can be considered a member of the perovskite-based An+1BnO3n1Cl homologous series (A = Pb/Bi; B = Fe) with n = 4. The formation of a subsequent member of the series with n = 5 is also demonstrated. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
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Place of Publication |
Easton, Pa |
Editor |
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Language |
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Wos |
000315255200067 |
Publication Date |
2013-02-05 |
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 |
|
ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.857 |
Times cited |
6 |
Open Access |
|
Notes |
Countatoms |
Approved |
Most recent IF: 4.857; 2013 IF: 4.794 |
Call Number |
UA @ lucian @ c:irua:106185 |
Serial |
1486 |
Permanent link to this record |
|
|
|
Author |
Shpanchenko, R.V.; Rozova, M.G.; Abakumov, A.M.; Ardashnikova, E.I.; Kovba, M.L.; Putilin, S.N.; Antipov, E.V.; Lebedev, O.I.; Van Tendeloo, G. |
Title |
Inducing superconductivity and structural transformations by fluorination of reduced YBCO |
Type |
A1 Journal article |
Year |
1997 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
Volume |
280 |
Issue |
|
Pages |
272-280 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
A1997XX21600005 |
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-4534 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.404 |
Times cited |
35 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.404; 1997 IF: 2.199 |
Call Number |
UA @ lucian @ c:irua:21449 |
Serial |
1604 |
Permanent link to this record |
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|
|
Author |
Croitoru, M.D.; Gladilin, V.N.; Fomin, V.M.; Devreese, J.T.; Kemerink, M.; Koenraad, P.M.; Sauthoff, K.; Wolter, J.H. |
Title |
Influence of the characteristics of the STM-tip on the electroluminescence spectra |
Type |
A1 Journal article |
Year |
2005 |
Publication |
Physica. E: Low-dimensional systems and nanostructures |
Abbreviated Journal |
Physica E |
Volume |
27 |
Issue |
|
Pages |
13-20 |
Keywords |
A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
North-Holland |
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000227813200003 |
Publication Date |
2004-12-16 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1386-9477; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
2.221 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.221; 2005 IF: 0.946 |
Call Number |
UA @ lucian @ c:irua:52793 |
Serial |
1645 |
Permanent link to this record |
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|
|
Author |
Morozov, V.A.; Lazoryak, B.I.; Shmurak, S.Z.; Kiselev, A.P.; Lebedev, O.I.; Gauquelin, N.; Verbeeck, J.; Hadermann, J.; Van Tendeloo, G. |
Title |
Influence of the structure on the properties of NaxEuy(MoO4)z red phosphors |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
26 |
Issue |
10 |
Pages |
3238-3248 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Scheelite related compounds (A',A '')(n)[(B',B '')O-4](m) with B', B '' = W and/or Mo are promising new materials for red phosphors in pc-WLEDs (phosphor-converted white-light-emitting-diode) and solid-state lasers. Cation substitution in CaMoO4 of Ca2+ by the combination of Na+ and Eu3+, with the creation of A cation vacancies, has been investigated as a factor for controlling the scheelite-type structure and the luminescent properties. Na5Eu(MoO4)(4) and NaxEu(2-x)/33+square(2-x)/3MoO4 (0.138 <= x <= 0.5) phases with a scheelite-type structure were synthesized by the solid state method; their structural characteristics were investigated using transmission electron microscopy. Contrary to powder synchrotron X-ray diffraction before, the study by electron diffraction and high resolution transmission electron microscopy in this paper revealed that Na0.286Eu0.571MoO4 has a (3 + 2)D incommensurately modulated structure and that (3 + 2)D incommensurately modulated domains are present in Na0.200Eu0.600MoO4. It also confirmed the (3 + 1)D incommensurately modulated character of Na(0.138)Eu(0.621)Mo04. The luminescent properties of all phases under near-ultraviolet (n-UV) light have been investigated. The excitation spectra of these phosphors show the strongest absorption at about 395 nm, which matches well with the commercially available n-UV-emitting GaN-based LED chip. The emission spectra indicate an intense red emission due to the D-5(0) -> F-7(2) transition of Eu3+, with local minima in the intensity at Na0.286Eu0.571MoO4 and Na0.200Eu0.600MoO4 for similar to 613 nm and similar to 616 nm bands. The phosphor Na5Eu(MoO4)(4) shows the brightest red light emission among the phosphors in the Na2MoO4-Eu2/3MoO4 system and the maximum luminescence intensity of Na5Eu(MoO4)(4) (lambda(ex) = 395 nm) in the D-5(0) -> F-7(2) transition region is close to that of the commercially used red phosphor YVO4:Eu3+ (lambda(ex) = 326 nm). Electron energy loss spectroscopy measurements revealed the influence of the structure and Na/Eu cation distribution on the number and positions of bands in the UV-optical-infrared regions of the EELS spectrum. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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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 |
000336637000028 |
Publication Date |
2014-05-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
53 |
Open Access |
|
Notes |
Fwo G039211n; Fwo G004413n; 278510 Vortex ECASJO_; |
Approved |
Most recent IF: 9.466; 2014 IF: 8.354 |
Call Number |
UA @ lucian @ c:irua:117765UA @ admin @ c:irua:117765 |
Serial |
1652 |
Permanent link to this record |
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|
|
Author |
Tsirlin, A.A.; Abakumov, A.M.; Van Tendeloo, G.; Rosner, H. |
Title |
Interplay of atomic displacement in the quantum magnet (CuCI)LaNb2O7 |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
82 |
Issue |
5 |
Pages |
054107,1-054107,12 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We report on the crystal structure of the quantum magnet CuClLaNb2O7 that was controversially described with respect to its structural organization and magnetic behavior. Using high-resolution synchrotron powder x-ray diffraction, electron diffraction, transmission electron microscopy, and band-structure calculations, we solve the room-temperature structure of this compound -CuClLaNb2O7 and find two high-temperature polymorphs. The -CuClLaNb2O7 phase, stable above 640 K, is tetragonal with asub=3.889 Å, csub =11.738 Å, and the space group P4/mmm. In the -CuClLaNb2O7 structure, the Cu and Cl atoms are randomly displaced from the special positions along the 100 directions. The phase asub2asubcsub, space group Pbmm and the phase 2asub2asubcsub, space group Pbam are stable between 640 K and 500 K and below 500 K, respectively. The structural changes at 500 and 640 K are identified as order-disorder phase transitions. The displacement of the Cl atoms is frozen upon the → transformation while a cooperative tilting of the NbO6 octahedra in the phase further eliminates the disorder of the Cu atoms. The low-temperature -CuClLaNb2O7 structure thus combines the two types of the atomic displacements that interfere due to the bonding between the Cu atoms and the apical oxygens of the NbO6 octahedra. The precise structural information resolves the controversy between the previous computation-based models and provides the long-sought input for understanding CuClLaNb2O7 and related compounds with unusual magnetic properties. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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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 |
000280849400001 |
Publication Date |
2010-08-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
13 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:83991 |
Serial |
1706 |
Permanent link to this record |
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|
Author |
Conings, B.; Drijkoningen, J.; Gauquelin, N.; Babayigit, A.; D'Haen, J.; D'Olieslaeger, L.; Ethirajan, A.; Verbeeck, J.; Manca, J.; Mosconi, E.; Angelis, F.D.; Boyen, H.G.; |
Title |
Intrinsic thermal instability of methylammonium lead trihalide perovskite |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Laser physics review |
Abbreviated Journal |
Adv Energy Mater |
Volume |
5 |
Issue |
5 |
Pages |
1500477 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Organolead halide perovskites currently are the new front-runners as light absorbers in hybrid solar cells, as they combine efficiencies passing already 20% with deposition temperatures below 100 °C and cheap solution-based fabrication routes. Long-term stability remains a major obstacle for application on an industrial scale. Here, it is demonstrated that significant decomposition effects already occur during annealing of a methylammonium lead triiode perovskite at 85 °C even in inert atmosphere thus violating international standards. The observed behavior supports the view of currently used perovskite materials as soft matter systems with low formation energies, thus representing a major bottleneck for their application, especially in countries with high average temperatures. This result can trigger a broader search for new perovskite families with improved thermal stability. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
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Place of Publication |
S.l. |
Editor |
|
Language |
|
Wos |
000359374900005 |
Publication Date |
2015-06-03 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1614-6832; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
16.721 |
Times cited |
1691 |
Open Access |
|
Notes |
FWO G004413N; GOA Solarpaint |
Approved |
Most recent IF: 16.721; 2015 IF: 16.146 |
Call Number |
c:irua:127298UA @ admin @ c:irua:127298 |
Serial |
1719 |
Permanent link to this record |
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Author |
van Vaeck, L.; Poels, K.; de Nollin, S.; Hachimi, A.; Gijbels, R. |
Title |
Laser microprobe mass spectrometry: principle and applications in biology and medicine |
Type |
A1 Journal article |
Year |
1997 |
Publication |
Cell biology international |
Abbreviated Journal |
Cell Biol Int |
Volume |
21 |
Issue |
|
Pages |
635-648 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
|
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000074882700003 |
Publication Date |
2002-10-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1065-6995; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.831 |
Times cited |
6 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.831; 1997 IF: 1.124 |
Call Number |
UA @ lucian @ c:irua:20464 |
Serial |
1797 |
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 ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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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 |
|
Series Issue |
|
Edition |
|
ISSN |
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 |
Lin, H.; Ohta, T.; Paul, A.; Hutchison, J.A.; Kirilenko, D.; Lebedev, O.; Van Tendeloo, G.; Hofkens, J.; Uji-i, H. |
Title |
Light-assisted nucleation of silver nanowires during polyol synthesis |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of photochemistry and photobiology: A: chemistry |
Abbreviated Journal |
J Photoch Photobio A |
Volume |
221 |
Issue |
2/3 |
Pages |
220-223 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
This report describes the effect of light irradiation on the synthesis of silver nanowires by the well-known polyol method. High quality nanowires are produced in high yields when the reaction suspension is irradiated with 400500 nm light during the nucleation stage. These studies suggest that light accelerates the formation of the nanoparticle seeds most appropriate for nanowire growth. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
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Place of Publication |
Lausanne |
Editor |
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Language |
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Wos |
000293813800018 |
Publication Date |
2011-04-19 |
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 |
1010-6030; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.625 |
Times cited |
24 |
Open Access |
|
Notes |
Fwo; Iap |
Approved |
Most recent IF: 2.625; 2011 IF: 2.421 |
Call Number |
UA @ lucian @ c:irua:91262 |
Serial |
1818 |
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 ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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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 |
|
Series Issue |
|
Edition |
|
ISSN |
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 |
Volkov, V.V.; Van Tendeloo, G.; Tsirkov, G.A.; Cherkashina, N.V.; Vargaftik, M.N.; Moiseev, I.I.; Novotortsev, V.M.; Kvit, A.V.; Chuvilin, A.L. |
Title |
Long- and short-distance ordering of the metal cores of giant Pd clusters |
Type |
A1 Journal article |
Year |
1996 |
Publication |
Journal of crystal growth |
Abbreviated Journal |
J Cryst Growth |
Volume |
163 |
Issue |
|
Pages |
377-387 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
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Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
A1996UW51100006 |
Publication Date |
2003-04-30 |
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 |
|
ISSN |
0022-0248; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.698 |
Times cited |
28 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:16866 |
Serial |
1834 |
Permanent link to this record |
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Author |
van Rossum, M.; Schoenmaker, W.; Magnus, W.; de Meyer, K.; Croitoru, M.D.; Gladilin, V.N.; Fomin, V.M.; Devreese, J.T. |
Title |
Moore's law: new playground for quantum physics |
Type |
A1 Journal article |
Year |
2003 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
Volume |
237 |
Issue |
|
Pages |
426-432 |
Keywords |
A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000182801800041 |
Publication Date |
2003-04-24 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
ISSN |
0370-1972;1521-3951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.674 |
Times cited |
2 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.674; 2003 IF: 0.987 |
Call Number |
UA @ lucian @ c:irua:44284 |
Serial |
2202 |
Permanent link to this record |
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Author |
Abakumov, A.M.; Tsirlin, A.A.; Bakaimi, I.; Van Tendeloo, G.; Lappas, A. |
Title |
Multiple twinning as a structure directing mechanism in layered rock-salt-type oxides : NaMnO2 polymorphism, redox potentials, and magnetism |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
26 |
Issue |
10 |
Pages |
3306-3315 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
New polymorphs of NaMnO2 have been observed using transmission electron microscopy and synchrotron X-ray powder diffraction. Coherent twin planes confined to the (NaMnO2) layers, parallel to the (10 (1) over bar) crystallographic planes of the monoclinic layered rock-salt-type alpha-NaMnO2 (O3) structure, form quasi-periodic modulated sequences, with the known alpha-and beta-NaMnO2 polymorphs as the two limiting cases. The energy difference between the polymorphic forms, estimated using a DFT-based structure relaxation, is on the scale of the typical thermal energies that results in a high degree of stacking disorder in these compounds. The results unveil the remarkable effect of the twin planes on both the magnetic and electrochemical properties. The polymorphism drives the magnetic ground state from a quasi-1D spin system for the geometrically frustrated alpha-polymorph through a two-leg spin ladder for the intermediate stacking sequence toward a quasi-2D magnet for the beta-polymorph. A substantial increase of the equilibrium potential for Na deintercalation upon increasing the concentration of the twin planes is calculated, providing a possibility to tune the electrochemical potential of the layered rock-salt ABO(2) cathodes by engineering the materials with a controlled concentration of twins. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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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 |
000336637000036 |
Publication Date |
2014-05-01 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
35 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 9.466; 2014 IF: 8.354 |
Call Number |
UA @ lucian @ c:irua:117766 |
Serial |
2232 |
Permanent link to this record |
|
|
|
Author |
Nistor, L.C.; van Landuyt, J.; Ralchenko, V.G.; Obratzova, E.D.; Smolin, A.A. |
Title |
Nanocrystalline diamond films: transmission electron microscopy and Raman spectroscopy characterization |
Type |
A1 Journal article |
Year |
1997 |
Publication |
Diamond and related materials |
Abbreviated Journal |
Diam Relat Mater |
Volume |
6 |
Issue |
|
Pages |
159-168 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
A1997WN37300021 |
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0925-9635 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.561 |
Times cited |
116 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.561; 1997 IF: 1.758 |
Call Number |
UA @ lucian @ c:irua:21406 |
Serial |
2249 |
Permanent link to this record |
|
|
|
Author |
Volkova, N.E.; Lebedev, O.I.; Gavrilova, L.Y.; Turner, S.; Gauquelin, N.; Seikh, M.M.; Caignaert, V.; Cherepanov, V.A.; Raveau, B.; Van Tendeloo, G. |
Title |
Nanoscale ordering in oxygen deficient quintuple perovskite Sm2-\epsilonBa3+\epsilonFe5O15-\delta : implication for magnetism and oxygen stoichiometry |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
26 |
Issue |
21 |
Pages |
6303-6310 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The investigation of the system SmBaFe-O in air has allowed an oxygen deficient perovskite Sm2-epsilon Ba3+epsilon Fe5O15-delta (delta = 0.75, epsilon = 0.125) to be synthesized. In contrast to the XRPD pattern which gives a cubic symmetry (a(p) = 3.934 angstrom), the combined HREM/EELS study shows that this phase is nanoscale ordered with a quintuple tetragonal cell, a(p) X a(p) X 5(ap). The nanodomains exhibit a unique stacking sequence of the A-site cationic layers along the crystallographic c-axis, namely SmBaBa/SmBa/SmBaSm, and are chemically twinned in the three crystallographic directions. The nanoscale ordering of this perovskite explains its peculiar magnetic properties on the basis of antiferromagnetic interactions with spin blockade at the boundary between the nanodomains. The variation of electrical conductivity and oxygen content of this oxide versus temperature suggest potential SOFC applications. They may be related to the particular distribution of oxygen vacancies in the lattice and to the 3d(5)(L) under bar configuration of iron. |
Address |
|
Corporate Author |
|
Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000344905600029 |
Publication Date |
2014-10-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
16 |
Open Access |
|
Notes |
The UrFU authors were financially supported by the Ministry of Education and Science of Russian Federation (project N 4.1039.2014/K) and by UrFU under the Framework Program of development of UrFU through the «Young scientists UrFU» competition. The CRISMAT authors gratefully acknowledge the EC, the CNRS and the French Minister of Education and Research for financial support through their Research, Strategic and Scholarship programs. This work was supported by funding from the European Research Council under the Seventh Framework Program (FP7), ERC grant N°246791 – COUNTATOMS. S.T. gratefully acknowledges the fund for scientific research Flanders for a post-doctoral fellowship and for financial support under contract number G004413N. N.G. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC starting grant number 278510 – VORTEX; ECASJO_; |
Approved |
Most recent IF: 9.466; 2014 IF: 8.354 |
Call Number |
UA @ lucian @ c:irua:122137 |
Serial |
2269 |
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 |
|
Address |
|
Corporate Author |
|
Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000331945200002 |
Publication Date |
2014-02-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
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 |
|
Notes |
|
Approved |
Most recent IF: 39.737; 2014 IF: 36.503 |
Call Number |
UA @ lucian @ c:irua:114579 |
Serial |
2270 |
Permanent link to this record |
|
|
|
Author |
Shpanchenko, R.V.; Tsirlin, A.A.; Kondakova, E.S.; Antipov, E.V.; Bougerol, C.; Hadermann, J.; Van Tendeloo, G.; Sakurai, H.; Takayama-Muromachi, E. |
Title |
New germanates RCrGeO5 (R=NdEr, Y): synthesis, structure, and properties |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
Volume |
181 |
Issue |
9 |
Pages |
2433-2441 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The new complex germanates RCrGeO5 (R=NdEr, Y) have been synthesized and investigated by means of X-ray powder diffraction, electron microscopy, magnetic susceptibility and specific heat measurements. All the compounds are isostructural and crystallize in the orthorhombic symmetry, space group Pbam, and Z=4. The crystal structure of RCrGeO5, as refined using X-ray powder diffraction data, includes infinite chains built by edge-sharing Cr+3O6 octahedra with two alternating Cr−Cr distances. The chains are combined into a three-dimensional framework by Ge2O8 groups consisting of two edge-linked square pyramids oriented in opposite directions. The resulting framework contains pentagonal channels where rare-earth elements are located. Thus, RCrGeO5 germanates present new examples of RMn2O5-type compounds and show ordering of Cr+3 and Ge+4 cations. Electron diffraction as well as high-resolution electron microscopy confirm the structure solution. Magnetic susceptibility data for R=Nd, Sm, and Eu are qualitatively consistent with the presence of isolated 3d (antiferromagnetically coupled Cr+3 cations) and 4f (R+3) spin subsystems in the RCrGeO5 compounds. NdCrGeO5 undergoes long-range magnetic ordering at 2.6 K, while SmCrGeO5 and EuCrGeO5 do not show any phase transitions down to 2 K. |
Address |
|
Corporate Author |
|
Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000259415800047 |
Publication Date |
2008-06-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-4596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.299 |
Times cited |
6 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.299; 2008 IF: 1.910 |
Call Number |
UA @ lucian @ c:irua:72948 |
Serial |
2314 |
Permanent link to this record |
|
|
|
Author |
Lin, F.; Meng; Kukueva, E.; Mertens, M.; Van Doorslaer, S.; Bals, S.; Cool, P. |
Title |
New insights into the mesophase transformation of ethane-bridged PMOs by the influence of different counterions under basic conditions |
Type |
A1 Journal article |
Year |
2015 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
Volume |
5 |
Issue |
5 |
Pages |
5553-5562 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
Abstract |
The counterions are of crucial importance in determining the mesostructure and morphology of ethanebridged PMO materials synthesized under basic conditions. By using CTABr as the surfactant, the final PMO materials show a 2-D hexagonal (p6mm) mesophase, while PMO materials with cubic (Pm (3) over barn ) mesostructure are obtained when CTACl or CTA(SO4)(1)/(2) are used. With gradually replacing CTABr by CTACl or CTA(SO4) (1)/(2) while keeping the total surfactant concentration constant, a clear p6mm to Pm (3) over barn 3n mesophase evolution process is observed. For a given gel composition, the mesophase of ethanebridged PMO materials can also be adjusted by the addition of different sodium salts. In short, the effect of the counterions on the mesophase can be attributed to the binding strength of the ions on the surfactant micelles, which follows the Hofmeister series (SO42- < Cl- < Br-< NO3- < SCN-). Furthermore, it is found that the hydrolysis and condensation rate of the organosilica precursor also plays an important role in the formation of the final mesostructure |
Address |
|
Corporate Author |
|
Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000347304900010 |
Publication Date |
2014-12-11 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2046-2069; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.108 |
Times cited |
6 |
Open Access |
Not_Open_Access |
Notes |
; The Erasmus Mundus CONNEC program is acknowledged for PhD funding of F. L. Furthermore, the authors acknowledge support by the GOA-BOF project 'Optimization of the structureactivity relation in nanoporous materials', funded by the University of Antwerp. ; |
Approved |
Most recent IF: 3.108; 2015 IF: 3.840 |
Call Number |
c:irua:123768 |
Serial |
2317 |
Permanent link to this record |
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|
|
Author |
Blin, J.L.; Becue, A.; Pauwels, B.; Van Tendeloo, G.; Su, B.L. |
Title |
Non-ionic surfactant (C13EOm, m=6, 12 and 18) for large pore mesoporous molecular sieves preparation |
Type |
A1 Journal article |
Year |
2001 |
Publication |
Microporous and mesoporous materials |
Abbreviated Journal |
Micropor Mesopor Mat |
Volume |
44/45 |
Issue |
|
Pages |
41-51 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000169557700007 |
Publication Date |
2002-07-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1387-1811; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.615 |
Times cited |
27 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.615; 2001 IF: 2.497 |
Call Number |
UA @ lucian @ c:irua:54789 |
Serial |
2346 |
Permanent link to this record |
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|
|
Author |
Wu, S.; Luo, X.; Turner, S.; Peng, H.; Lin, W.; Ding, J.; David, A.; Wang, B.; Van Tendeloo, G.; Wang, J.; Wu, T.; |
Title |
Nonvolatile resistive switching in Pt/LaAlO3/SrTiO3 heterostructures |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physical review X |
Abbreviated Journal |
Phys Rev X |
Volume |
3 |
Issue |
4 |
Pages |
041027-14 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Resistive switching heterojunctions, which are promising for nonvolatile memory applications, usually share a capacitorlike metal-oxide-metal configuration. Here, we report on the nonvolatile resistive switching in Pt/LaAlO3/SrTiO3 heterostructures, where the conducting layer near the LaAlO3/SrTiO3 interface serves as the unconventional bottom electrode although both oxides are band insulators. Interestingly, the switching between low-resistance and high-resistance states is accompanied by reversible transitions between tunneling and Ohmic characteristics in the current transport perpendicular to the planes of the heterojunctions. We propose that the observed resistive switching is likely caused by the electric-field-induced drift of charged oxygen vacancies across the LaAlO3/SrTiO3 interface and the creation of defect-induced gap states within the ultrathin LaAlO3 layer. These metal-oxide-oxide heterojunctions with atomically smooth interfaces and defect-controlled transport provide a platform for the development of nonvolatile oxide nanoelectronics that integrate logic and memory devices. |
Address |
|
Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
|
Place of Publication |
College Park, Md |
Editor |
|
Language |
|
Wos |
000328862400001 |
Publication Date |
2013-12-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2160-3308; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.789 |
Times cited |
77 |
Open Access |
|
Notes |
FWO;FP7;IFOX; Countatoms; Hercules |
Approved |
Most recent IF: 12.789; 2013 IF: 8.463 |
Call Number |
UA @ lucian @ c:irua:112524 |
Serial |
2365 |
Permanent link to this record |
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|
|
Author |
Lin, F.; Meng, X.; Kukueva, E.; Kus, M.; Mertens, M.; Bals, S.; Van Doorslaer, S.; Cool, P. |
Title |
Novel method to synthesize highly ordered ethane-bridged PMOs under mild acidic conditions : taking advantages of phosphoric acid |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Microporous and mesoporous materials: zeolites, clays, carbons and related materials |
Abbreviated Journal |
Micropor Mesopor Mat |
Volume |
207 |
Issue |
207 |
Pages |
61-70 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
Abstract |
Highly ordered SBA-15-type ethane-bridged PMOs have been obtained by employing H3PO4 as acid to tune the pH in the presence of copolymer surfactant P123. The effects of the acidity and the addition of inorganic salt on the formation of the mesostructure are investigated. It is found that, compared with HCl, the polyprotic weak acid H3PO4 is preferable for the synthesis of highly ordered SBA-15-type ethane-bridged PMOs with larger pore size and surface areas under mild acidic conditions. Moreover, taking the advantages of the mild acidic condition, vanadium-containing SBA-15-type ethane-bridged PMOs were successfully prepared through a direct synthesis approach. The XRD, N2-sorption, UVVis and CW-EPR studies of the V-PMO show that part of the vanadium species are present in polymeric (VOV)n clusters, while part of the vanadium centers are well-dispersed and immobilized on the inner surface of the mesopores. |
Address |
|
Corporate Author |
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Thesis ![sorted by Thesis field, descending order (down)](img/sort_desc.gif) |
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Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000350518600009 |
Publication Date |
2015-01-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1387-1811; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.615 |
Times cited |
5 |
Open Access |
OpenAccess |
Notes |
; The Erasmus Mundus CONNEC program is acknowledged for PhD funding of F.Lin. Furthermore, the authors acknowledge support by the GOA-BOF project 'Optimization of the structure-activity relation in nanoporous materials', funded by the University of Antwerp. ; |
Approved |
Most recent IF: 3.615; 2015 IF: 3.453 |
Call Number |
c:irua:123910 |
Serial |
2379 |
Permanent link to this record |