Records |
Author |
Milat, O.; Van Tendeloo, G.; Amelinckx, S.; Wright, A.J.; Greaves, C. |
Title |
Effect of the substitution Ba\leftrightarrow Sr on the Ga-1222 superstructure : an electron diffraction study |
Type |
A1 Journal article |
Year |
1995 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
7 |
Issue |
9 |
Pages |
1709-1715 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The superstructure of the RE(2)(Sr0.85-xBaxNd0.15)(2)GaCU2O9 compound is found to change significantly with increasing substitution of Ba for Sr. Most of the changes take place in the (Sr0.85-xBaxNd0.15)O-GaO-(Sr0.85-xBaxNd0.15)O lamella, the rest of the basic structure being hardly affected. The structural changes for O less than or equal to x less than or equal to 0.65 are studied by electron diffraction. The arrangement of the chains of GaO4 tetrahedra in the Ba-free compound becomes disordered at x > 0.25. At x similar to 0.65 a rearrangement of the chains in the GaO layers takes place; they form a meandering arrangement, which can be described on a 4a(p) x 2a(p) x c(p) superlattice. This rearrangement is accompanied by ordering of Ba and Sr atoms in the adjacent (ST0.85-xBaxNd0.15)O layers. A simple scheme is proposed to explain the influence of the substitution of Ba for Sr on the linking of the GaO4 tetrahedra and on the geometry of the ''chains'' in the GaO layer. |
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 |
A1995RW21200021 |
Publication Date |
2005-03-08 |
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 |
0897-4756;1520-5002; |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
8.354 |
Times cited ![sorted by Times cited field, descending order (down)](img/sort_desc.gif) |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ lucian @ c:irua:13326 |
Serial |
850 |
Permanent link to this record |
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Author |
Feng, H.L.; Kang, C.-J.; Manuel, P.; Orlandi, F.; Su, Y.; Chen, J.; Tsujimoto, Y.; Hadermann, J.; Kotliar, G.; Yamaura, K.; McCabe, E.E.; Greenblatt, M. |
Title |
Antiferromagnetic order breaks inversion symmetry in a metallic double perovskite, Pb₂NiOsO₆ |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Chemistry Of Materials |
Abbreviated Journal |
Chem Mater |
Volume |
33 |
Issue |
11 |
Pages |
4188-4195 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A polycrystalline sample of Pb2NiOsO6 was synthesized under high-pressure (6 GPa) and high-temperature (1575 K) conditions. Pb2NiOsO6 crystallizes in a monoclinic double perovskite structure with a centrosymmetric space group P2(1)/n at room temperature. Pb2NiOsO6 is metallic down to 2 K and shows a single antiferromagnetic (AFM) transition at T-N = 58 K. Pb2NiOsO6 is a new example of a metallic and AFM oxide with three-dimensional connectivity. Neutron powder diffraction and first-principles calculation studies indicate that both Ni and Os moments are ordered below T-N and the AFM magnetic order breaks inversion symmetry. This loss of inversion symmetry driven by AFM order is unusual in metallic systems, and the 3d-Sd double-perovskite oxides represent a new class of noncentrosymmetric AFM metallic oxides. |
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 |
000661521800032 |
Publication Date |
2021-05-26 |
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 |
0897-4756; 1520-5002 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited ![sorted by Times cited field, descending order (down)](img/sort_desc.gif) |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 9.466 |
Call Number |
UA @ admin @ c:irua:179679 |
Serial |
6854 |
Permanent link to this record |
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Author |
Hao, Y.; Velpula, G.; Kaltenegger, M.; Bodlos, W.R.; Vibert, F.; Mali, K.S.; De Feyter, S.; Resel, R.; Geerts, Y.H.; Van Aert, S.; Beljonne, D.; Lazzaroni, R. |
Title |
From 2D to 3D : bridging self-assembled monolayers to a substrate-induced polymorph in a molecular semiconductor |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
34 |
Issue |
5 |
Pages |
2238-2248 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
In this study, a new bottom-up approach is proposed to predict the crystal structure of the substrate-induced polymorph (SIP) of an archetypal molecular semiconductor. In spite of intense efforts, the formation mechanism of SIPs is still not fully understood, and predicting their crystal structure is a very delicate task. Here, we selected lead phthalocyanine (PbPc) as a prototypical molecular material because it is a highly symmetrical yet nonplanar molecule and we demonstrate that the growth and crystal structure of the PbPc SIPs can be templated by the corresponding physisorbed self-assembled molecular networks (SAMNs). Starting from SAMNs of PbPc formed at the solution/graphite interface, the structural and energetic aspects of the assembly were studied by a combination of in situ scanning tunneling microscopy and multiscale computational chemistry approach. Then, the growth of a PbPc SIP on top of the physisorbed monolayer was modeled without prior experimental knowledge, from which the crystal structure of the SIP was predicted. The theoretical prediction of the SIP was verified by determining the crystal structure of PbPc thin films using X-ray diffraction techniques, revealing the formation of a new polymorph of PbPc on the graphite substrate. This study clearly illustrates the correlation between the SAMNs and SIPs, which are traditionally considered as two separate but conceptually connected research areas. This approach is applicable to molecular materials in general to predict the crystal structure of their SIPs. |
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 |
000812125800001 |
Publication Date |
2022-02-17 |
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 |
0897-4756; 1520-5002 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.6 |
Times cited ![sorted by Times cited field, descending order (down)](img/sort_desc.gif) |
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Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: 8.6 |
Call Number |
UA @ admin @ c:irua:189086 |
Serial |
7084 |
Permanent link to this record |