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Author Bittencourt, C.; Felten, A.; Ghijsen, J.; Pireaux, J.-J.; Drube, W.; Erni, R.; Van Tendeloo, G.
Title Decorating carbon nanotubes with nickel nanoparticles Type A1 Journal article
Year 2007 Publication Chemical physics letters Abbreviated Journal (down) Chem Phys Lett
Volume 436 Issue 4/6 Pages 368-372
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000245302000013 Publication Date 2007-01-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 78 Open Access
Notes Ia-Sfs; Pai 5/1 Approved Most recent IF: 1.815; 2007 IF: 2.207
Call Number UA @ lucian @ c:irua:64310 Serial 611
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Author Lamoen, D.; Parrinello, M.
Title Geometry and electronic structure of porphyrines and porphyrazines Type A1 Journal article
Year 1996 Publication Chemical Physics Letters Abbreviated Journal (down) Chem Phys Lett
Volume 248 Issue Pages 309
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos A1996TR41900002 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.897 Times cited 46 Open Access
Notes Approved CHEMISTRY, PHYSICAL 88/144 Q3 # PHYSICS, ATOMIC, MOLECULAR & CHEMICAL 19/35 Q3 #
Call Number UA @ lucian @ c:irua:15821 Serial 1329
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Author Colomer, J.F.; Stephan, C.; Lefrant, S.; Van Tendeloo, G.; Willems, I.; Konya, Z.; Fonseca, A.; Laurent, C.; Nagy, J.B.
Title Large-scale synthesis of single-wall carbon nanotubes by catalytic chemical vapor deposition (CCVD) method Type A1 Journal article
Year 2000 Publication Chemical physics letters Abbreviated Journal (down) Chem Phys Lett
Volume 317 Issue 1-2 Pages 83-89
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The large-scale production of single-wall carbon nanotubes (SWNTs) is reported. Large quantities of SWNTs can be synthesised by catalytic decomposition of methane over well-dispersed metal particles supported on MgO at 1000 degrees C. The thus produced SWNTs can be separated easily from the support by a simple acidic treatment to obtain a product with high yields (70-80%) of SWNTs. Because the typical synthesis time is 10 min, 1 g of SWNTs can be synthesised per day by this method. The SWNTs are characterized by high-resolution transmission electron microscopy and by Raman spectroscopy, showing the quality and the quantity of products. (C) 2000 Elsevier Science B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000085128300015 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 344 Open Access
Notes Approved Most recent IF: 1.815; 2000 IF: 2.364
Call Number UA @ lucian @ c:irua:103957 Serial 1782
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Author Bittencourt, C.; Ke, X.; Van Tendeloo, G.; Tagmatarchis, N.; Guttmann, P.
Title NEXAFS spectromicroscopy of suspended carbon nanohorns Type A1 Journal article
Year 2013 Publication Chemical physics letters Abbreviated Journal (down) Chem Phys Lett
Volume 587 Issue Pages 85-87
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We demonstrate that near-edge X-ray-absorption fine-structure spectroscopy combined with full-field transmission X-ray microscopy can be used to study the electronic structure of suspended carbon nanohorns. Based on reports of electronic structure calculations additional spectral features observed in the π region of the NEXAFS spectrum recorded on the carbon nanohorns were associated to the presence of the pentagonal rings and the folding of the graphene sheet.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000326104500016 Publication Date 2013-09-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 4 Open Access
Notes Fp7; Countatoms; Approved Most recent IF: 1.815; 2013 IF: 1.991
Call Number UA @ lucian @ c:irua:111592 Serial 2339
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Author Adjizian, J.J.; De Marco, P.; Suarez-Martinez, I.; El Mel, A.A.; Snyders, R.; Gengler, R.Y.N.; Rudolf, P.; Ke, X.; Van Tendeloo, G.; Bittencourt, C.; Ewels, C.P.;
Title Platinum and palladium on carbon nanotubes : experimental and theoretical studies Type A1 Journal article
Year 2013 Publication Chemical physics letters Abbreviated Journal (down) Chem Phys Lett
Volume 571 Issue Pages 44-48
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Pristine and oxygen plasma functionalised carbon nanotubes (CNTs) were studied after the evaporation of Pt and Pd atoms. High resolution transmission electron microscopy shows the formation of metal nanoparticles at the CNT surface. Oxygen functional groups grafted by the plasma functionalization act as nucleation sites for metal nanoparticles. Analysis of the C1s core level spectra reveals that there is no covalent bonding between the Pt or Pd atoms and the CNT surface. Unlike other transition metals such as titanium and copper, neither Pd nor Pt show strong oxygen interaction or surface oxygen scavenging behaviour.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000319109900007 Publication Date 2013-04-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 23 Open Access
Notes Countatoms; Cost Approved Most recent IF: 1.815; 2013 IF: 1.991
Call Number UA @ lucian @ c:irua:108706 Serial 2650
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Author Bittencourt, C.; Hecq, M.; Felten, A.; Pireaux, J.J.; Ghijsen, J.; Felicissimo, M.P.; Rudolf, P.; Drube, W.; Ke, X.; Van Tendeloo, G.
Title Platinumcarbon nanotube interaction Type A1 Journal article
Year 2008 Publication Chemical physics letters Abbreviated Journal (down) Chem Phys Lett
Volume 462 Issue 4/6 Pages 260-264
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The interaction between evaporated Pt and pristine or oxygen-plasma-treated multiwall carbon nanotubes (CNTs) is investigated. Pt is found to nucleate at defect sites, whether initially present or introduced by oxygen plasma treatment. The plasma treatment induces a uniform dispersion of Pt nanoparticles at the CNT surface. The absence of additional features in the C 1s core level spectrum indicates that no mixed PtC phase is formed. The formation of COPt bonds at the cluster-CNT interface is suggested to reduce the electronic interaction between Pt nanoparticles and the CNT surface.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000258830900025 Publication Date 2008-07-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 62 Open Access
Notes Pai Approved Most recent IF: 1.815; 2008 IF: 2.169
Call Number UA @ lucian @ c:irua:76489 Serial 2652
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Author Pierard, N.; Fonseca, A.; Konya, Z.; Willems, I.; Van Tendeloo, G.; Nagy, J.B.
Title Production of short carbon nanotubes with open tips by ball milling Type A1 Journal article
Year 2001 Publication Chemical physics letters Abbreviated Journal (down) Chem Phys Lett
Volume 335 Issue Pages 1-8
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000167018700001 Publication Date 2002-10-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 203 Open Access
Notes Approved Most recent IF: 1.815; 2001 IF: 2.364
Call Number UA @ lucian @ c:irua:54774 Serial 2725
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Author Massobrio, C.; Djimbi, D.M.; Matsubara, M.; Scipioni, R.; Boero, M.
Title Stability of Ge12C48 and Ge20C40 heterofullerenes : a first principles molecular dynamics study Type A1 Journal article
Year 2013 Publication Chemical physics letters Abbreviated Journal (down) Chem Phys Lett
Volume 556 Issue Pages 163-167
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract By using first-principles molecular dynamics, we address the issue of structural stability for the C-60 Ge-m(m) family of doped heterofullerenes through a set of calculations targeting C48Ge12 and C40Ge20. Three kinds of theoretical tools are employed: (a) static structural optimization, (b) a bonding analysis based on localized orbitals (Wannier wavefunctions and centers) and (c) first-principles molecular dynamics at finite temperature. This latter tool allows concluding that the segregated form of C40Ge20 is less stable than its Si-based counterpart. However, the non-segregated forms of C40Ge20 and C40Si20 have comparable stabilities at finite temperatures. (C) 2012 Elsevier B. V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000313644100032 Publication Date 2012-11-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 3 Open Access
Notes Approved Most recent IF: 1.815; 2013 IF: 1.991
Call Number UA @ lucian @ c:irua:110085 Serial 3132
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Author Ivanov, V.; Nagy, J.B.; Lambin, P.; Lucas, A.; Zhang, X.B.; Zhang, X.F.; Bernaerts, D.; Van Tendeloo, G.; Amelinckx, S.; van Landuyt, J.
Title The study of carbon nanotubes produced by catalytic method Type A1 Journal article
Year 1994 Publication Chemical physics letters Abbreviated Journal (down) Chem Phys Lett
Volume 223 Issue Pages 329-335
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos A1994NT08000011 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.897 Times cited 405 Open Access
Notes Approved PHYSICS, APPLIED 28/145 Q1 #
Call Number UA @ lucian @ c:irua:10002 Serial 3326
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Author Bittencourt, C.; Ke, X.; Van Tendeloo, G.; Thiess, S.; Drube, W.; Ghijsen, J.; Ewels, C.P.
Title Study of the interaction between copper and carbon nanotubes Type A1 Journal article
Year 2012 Publication Chemical physics letters Abbreviated Journal (down) Chem Phys Lett
Volume 535 Issue Pages 80-83
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Copper deposited by thermal evaporation onto pristine and oxygen plasma treated carbon nanotubes (CNTs) diffuse over the CNT surface, coalescing and forming crystalline islands. The nucleation sites of the islands are preferentially defects, and more homogeneous island dispersion was observed at the CNT oxygen functionalized surface. The presence of weakly bound oxygen atoms at the CNT surface induces the formation of CuO bonds at the Cu/CNT interface, as described through density functional calculations. Exposure to air allows further oxidation to facetted crystalline Cu2O. Oxygen plasma pre-treatment represents a promising route for homogenous disperse Cu2O nanoparticle decoration of CNTs.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000303437900015 Publication Date 2012-03-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 27 Open Access
Notes Approved Most recent IF: 1.815; 2012 IF: 2.145
Call Number UA @ lucian @ c:irua:97704 Serial 3336
Permanent link to this record
 

 
Author Du, G.H.; Van Tendeloo, G.
Title Cu(OH)2 nanowires, CuO nanowires and CuO nanobelts Type A1 Journal article
Year 2004 Publication Chemical physics letters Abbreviated Journal (down) Chem Phys Lett
Volume 393 Issue 1/3 Pages 64-69
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000222887700012 Publication Date 2004-06-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 145 Open Access
Notes Iuap P5/01 Approved Most recent IF: 1.815; 2004 IF: 2.438
Call Number UA @ lucian @ c:irua:54777 Serial 3525
Permanent link to this record
 

 
Author Ivanov, V.; Nagy, J.B.; Lambin, P.; Lucas, A.; Zhang, X.B.; Zhang, X.F.; Bernaerts, D.; Van Tendeloo, G.; Amelinckx, S.; van Landuyt, J.
Title The study of carbon nanotubules produced by catalytic method Type A1 Journal article
Year 1994 Publication Chemical physics letters Abbreviated Journal (down) Chem Phys Lett
Volume 223 Issue 4 Pages 329-335
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Catalytic methods for the production of carbon nanotubules have been developed based on the decomposition of acetylene on well-dispersed metal particles strongly adsorbed on a support. Cobalt on silica was found to be the best catalyst-support combination for the production of graphitic tubules. The method for the catalyst preparation and the reaction conditions were optimized. Straight and coiled carbon tubules were obtained with inner and outer diameter of 3-7 and 15-20 nm, respectively, and up to 30 mum in length. These nanotubules were not coated by amorphous carbon. Traces of amorphous carbon could be removed by hydrogen. High resolution electron microscopy images and electron diffraction patterns of the straight nanotubules were similar to those obtained by the arc-discharge method. Coiled nanotubules were revealed by TEM to be regular polygonized helices where the bends are caused by pairs of pentagon-heptagon carbon rings among the hexagonal network.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos A1994NT08000011 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.897 Times cited 405 Open Access
Notes Approved PHYSICS, APPLIED 47/145 Q2 #
Call Number UA @ lucian @ c:irua:99869 Serial 3595
Permanent link to this record
 

 
Author Scipioni, R.; Matsubara, M.; Ruiz, E.; Massobrio, C.; Boero, M.
Title Thermal behavior of Si-doped fullerenes vs their structural stability at T = 0 K : a density functional study Type A1 Journal article
Year 2011 Publication Chemical physics letters Abbreviated Journal (down) Chem Phys Lett
Volume 510 Issue 1/3 Pages 14-17
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We establish the topological conditions underlying the thermal stability of C30Si30 clusters. Two topologies have been considered: a segregated one, where Si and C atoms lie on neighboring and yet, separated parts of the cage, and a non-segregated one, where the number of SiC bonds is maximized. The segregated network is energetically favored against the non-segregated one, both structures being fully relaxed at T = 0 K. Conversely, the non-segregated structure is the only one stable at finite temperatures, regardless of the nature of the local states (d or p) included in the KleynmanBylander construction.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000291478400002 Publication Date 2011-05-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 14 Open Access
Notes Approved Most recent IF: 1.815; 2011 IF: 2.337
Call Number UA @ lucian @ c:irua:90453 Serial 3625
Permanent link to this record
 

 
Author Verheijen, M.A.; Meekes, H.; Meijer, G.; Bennema, P.; de Boer, J.L.; van Smaalen, S.; Van Tendeloo, G.; Amelinckx, S.; Muto, S.; van Landuyt, J.
Title The structure of different phases of pure C70 crystals Type A1 Journal article
Year 1992 Publication Chemical physics Abbreviated Journal (down) Chem Phys
Volume 166 Issue Pages 287-297
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos A1992JQ46300026 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0301-0104; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.652 Times cited 168 Open Access
Notes Approved PHYSICS, APPLIED 28/145 Q1 #
Call Number UA @ lucian @ c:irua:4104 Serial 3309
Permanent link to this record
 

 
Author Corbel, G.; Attfield, J.P.; Hadermann, J.; Abakumov, A.M.; Alekseeva, A.M.; Rozova, M.G.; Antipov, E.V.
Title Anion rearrangements in fluorinated Nd2CuO3.5 Type A1 Journal article
Year 2003 Publication Chemistry of materials Abbreviated Journal (down) Chem Mater
Volume 15 Issue Pages 189-195
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000180368000029 Publication Date 2003-01-07
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 9 Open Access
Notes Approved Most recent IF: 9.466; 2003 IF: 4.374
Call Number UA @ lucian @ c:irua:40348 Serial 123
Permanent link to this record
 

 
Author Casavola, M.; van Huis, M.A.; Bals, S.; Lambert, K.; Hens, Z.; Vanmaekelbergh, D.
Title Anisotropic cation exchange in PbSe/CdSe core/shell nanocrystals of different geometry Type A1 Journal article
Year 2012 Publication Chemistry of materials Abbreviated Journal (down) Chem Mater
Volume 24 Issue 2 Pages 294-302
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We present a study of Cd2+-for-Pb2+ exchange in PbSe nanocrystals (NCs) with cube, star, and rod shapes. Prolonged temperature-activated cation exchange results in PbSe/CdSe heterostructured nanocrystals (HNCs) that preserve their specific overall shape, whereas the PbSe core is strongly faceted with dominance of {111} facets. Hence, cation exchange proceeds while the Se anion lattice is preserved, and well-defined {111}/{111} PbSe/CdSe interfaces develop. Interestingly, by quenching the reaction at different stages of the cation exchange new structures have been isolated, such as coreshell nanorods, CdSe rods that contain one or two separated PbSe dots and fully zinc blende CdSe nanorods. The crystallographically anisotropic cation exchange has been characterized by a combined HRTEM/HAADF-STEM study of heterointerface evolution over reaction time and temperature. Strikingly, Pb and Cd are only intermixed at the PbSe/CdSe interface. We propose a plausible model for the cation exchange based on a layer-by-layer replacement of Pb2+ by Cd2+ enabled by a vacancy-assisted cation migration mechanism.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000299367500008 Publication Date 2011-11-17
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 136 Open Access
Notes Esteem 026019 Approved Most recent IF: 9.466; 2012 IF: 8.238
Call Number UA @ lucian @ c:irua:94211 Serial 124
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Author Abakumov, A.M.; Batuk, D.; Hadermann, J.; Rozova, M.G.; Sheptyakov, D.V.; Tsirlin, A.A.; Niermann, D.; Waschowski, F.; Hemberger, J.; Van Tendeloo, G.; Antipov, E.V.
Title Antiferroelectric (Pb,Bi)1-xFe1+xO3-y perovskites modulated by crystallographic shear planes Type A1 Journal article
Year 2011 Publication Chemistry of materials Abbreviated Journal (down) Chem Mater
Volume 23 Issue 2 Pages 255-265
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We demonstrate for the first time a possibility to vary the anion content in perovskites over a wide range through a long-range-ordered arrangement of crystallographic shear (CS) planes. Anion-deficient perovskites (Pb,Bi)1−xFe1+xO3−y with incommensurately modulated structures were prepared as single phases in the compositional range from Pb0.857Bi0.094Fe1.049O2.572 to Pb0.409Bi0.567Fe1.025O2.796. Using a combination of electron diffraction and high-resolution scanning transmission electron microscopy, we constructed a superspace model describing a periodic arrangement of the CS planes. The model was verified by refinement of the Pb0.64Bi0.32Fe1.04O2.675 crystal structure from neutron powder diffraction data ((3 + 1)D S.G. X2/m(α0γ), X = [1/2,1/2,1/2,1/2], a = 3.9082(1) Å, b = 3.90333(8) Å, c = 4.0900(1) Å, β = 91.936(2)°, q = 0.05013(4)a* + 0.09170(3)c* at T = 700 K, RP = 0.036, RwP = 0.048). The (Pb,Bi)1−xFe1+xO3−y structures consist of perovskite blocks separated by CS planes confined to nearly the (509)p perovskite plane. Along the CS planes, the perovskite blocks are shifted with respect to each other over the 1/2[110]p vector that transforms the corner-sharing connectivity of the FeO6 octahedra in the perovskite framework to an edge-sharing connectivity of the FeO5 pyramids at the CS plane, thus reducing the oxygen content. Variation of the chemical composition in the (Pb,Bi)1−xFe1+xO3−y series occurs mainly because of a changing thickness of the perovskite block between the interfaces, that can be expressed through the components of the q vector as Pb6γ+2αBi1−7γ−αFe1+γ−αO3−3γ−α. The Pb, Bi, and Fe atoms are subjected to strong displacements occurring in antiparallel directions on both sides of the perovskite blocks, resulting in an antiferroelectric-type structure. This is corroborated by the temperature-, frequency-, and field-dependent complex permittivity measurements. Pb0.64Bi0.32Fe1.04O2.675 demonstrates a remarkably high resistivity >0.1 T Ω cm at room temperature and orders antiferromagnetically below TN = 608(10) K.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000286160800018 Publication Date 2010-12-23
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 29 Open Access
Notes Approved Most recent IF: 9.466; 2011 IF: 7.286
Call Number UA @ lucian @ c:irua:88651 Serial 136
Permanent link to this record
 

 
Author Belik, A.A.; Abakumov, A.M.; Tsirlin, A.A.; Hadermann, J.; Kim, J.; Van Tendeloo, G.; Takayama-Muromachi, E.
Title Article Structure and magnetic properties of BiFe0.75Mn0.25O3 perovskite prepared at ambient and high pressure Type A1 Journal article
Year 2011 Publication Chemistry of materials Abbreviated Journal (down) Chem Mater
Volume 23 Issue 20 Pages 4505-4514
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Solid solutions of BiFe1xMnxO3 (0.0 ≤ x ≤ 0.4) were prepared at ambient pressure and at 6 GPa. The ambient-pressure (AP) phases crystallize in space group R3c similarly to BiFeO3. The high-pressure (HP) phases crystallize in space group R3c for x = 0.05 and in space group Pnma for 0.15 ≤ x ≤ 0.4. The structure of HP-BiFe0.75Mn0.25O3 was investigated using synchrotron X-ray powder diffraction, electron diffraction, and transmission electron microscopy. HP-BiFe0.75Mn0.25O3 has a PbZrO3-related √2ap × 4ap × 2√2ap (ap is the parameter of the cubic perovskite subcell) superstructure with a = 5.60125(9) Å, b = 15.6610(2) Å, and c = 11.2515(2) Å similar to that of Bi0.82La0.18FeO3. A remarkable feature of this structure is the unconventional octahedral tilt system, with the primary ab0a tilt superimposed on pairwise clockwise and counterclockwise rotations around the b-axis according to the oioi sequence (o stands for out-of-phase tilt, and i stands for in-phase tilt). The (FeMn)O6 octahedra are distorted, with one longer metaloxygen bond (2.222.23 Å) that can be attributed to a compensation for covalent BiO bonding. Such bonding results in the localization of the lone electron pair on Bi3+ cations, as confirmed by electron localization function analysis. The relationship between HP-BiFe0.75Mn0.25O3 and antiferroelectric structures of PbZrO3 and NaNbO3 is discussed. On heating in air, HP-BiFe0.75Mn0.25O3 irreversibly transforms to AP-BiFe0.75Mn0.25O3 starting from about 600 K. Both AP and HP phases undergo an antiferromagnetic ordering at TN ≈ 485 and 520 K, respectively, and develop a weak net magnetic moment at low temperatures. Additionally, ceramic samples of AP-BiFe0.75Mn0.25O3 show a peculiar phenomenon of magnetization reversal.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000295897400015 Publication Date 2011-09-29
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 57 Open Access
Notes Approved Most recent IF: 9.466; 2011 IF: 7.286
Call Number UA @ lucian @ c:irua:93581 Serial 151
Permanent link to this record
 

 
Author Turner, S.; Verbeeck, J.; Ramezanipour, F.; Greedan, J.E.; Van Tendeloo, G.; Botton, G.A.
Title Atomic resolution coordination mapping in Ca2FeCoO5 brownmillerite by spatially resolved electron energy-loss spectroscopy Type A1 Journal article
Year 2012 Publication Chemistry of materials Abbreviated Journal (down) Chem Mater
Volume 24 Issue 10 Pages 1904-1909
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Using a combination of high-angle annular dark field scanning transmission electron microscopy and atomically resolved electron energy-loss spectroscopy at high energy resolution in an aberration-corrected electron microscope, we demonstrate the capability of coordination mapping in complex oxides. Brownmillerite compound Ca2FeCoO5, consisting of repetitive octahedral and tetrahedral coordination layers with Fe and Co in a fixed 3+ valency, is selected to demonstrate the principle of atomic resolution coordination mapping. Analysis of the Co-L2,3 and the Fe-L2,3 edges shows small variations in the fine structure that can be specifically attributed to Co/Fe in tetrahedral or in octahedral coordination. Using internal reference spectra, we show that the coordination of the Fe and Co atoms in the compound can be mapped at atomic resolution.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000304237500024 Publication Date 2012-04-25
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 33 Open Access
Notes A.M. Abakumov is thanked for fruitful discussions. S.T. gratefully acknowledges the Fund for Scientific Research Flanders (FWO). J.E.G. and GAB. acknowledge the support of the NSERC of Canada through Discovery Grants. The Canadian Centre for Electron Microscopy is a National Facility supported by NSERC and McMaster University and was funded by the Canada Foundation for Innovation and the Ontario Government. Part of this work was supported by funding from the European Research Council under the FP7, ERC Grant N 246791 COUNTATOMS and ERC Starting Grant N 278510 VORTEX. The EMAT microscope is partially funded by the Hercules fund of the Flemish Government. ECASJO_; Approved Most recent IF: 9.466; 2012 IF: 8.238
Call Number UA @ lucian @ c:irua:98379UA @ admin @ c:irua:98379 Serial 175
Permanent link to this record
 

 
Author Esken, D.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Fischer, R.A.
Title Au@ZIFs: stabilization and encapsulation of cavity-size matching gold clusters inside functionalized Zeolite Imidazolate Frameworks, ZIFs Type A1 Journal article
Year 2010 Publication Chemistry of materials Abbreviated Journal (down) Chem Mater
Volume 22 Issue 23 Pages 6393-6401
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The selective formation and stabilization of very small, naked metal particles inside the cavities of metal organic frameworks (MOFs) and the simultaneous realization of an even distribution of the particles throughout the crystalline MOF host matrix over a wide range of metal loading are challenging goals. MOFs reveal high specific surface areas, tunable pore sizes, and organic linkers, which are able to interact with guests. The chemically very robust zeolite imidazolate frameworks (ZIFs) are a subclass of MOFs. We chose the microporous sodalite-like ZIF-8 (Zn(MelM)(2); IM = imidazolate) and ZIF-90 (Zn(ICA)(2); ICA = imidazolate-2-carboxyaldehyde) as host matrices to influence the dispersion of imbedded gold nanoparticles (Au NPs). The metal loading was achieved via gas phase infiltration of [Au(CO)Cl] followed by a thermal hydrogenation step to form the Au NPs. Low-dose high-resolution transmission electron microscopy ((HR)TEM) and electron tomography reveal a homogeneous distribution of Au NPs throughout the ZIF matrix. The functional groups of ZIF-90 direct the anchoring of intermediate Au species and stabilize drastically smaller and quite monodisperse Au NPs in contrast to the parent not functionalized ZIF-8. The particles can be very small, match the cavity size and approach defined molecular clusters of magic numbers, i.e., Au(55), independently from the level of loading. Post-synthetic oxidation of the aldehyde groups to yield alkyl esters by the adjacent, catalytically active metal NPs is presented as a new concept of encapsulating nanoparticles inside MOFs and allows multiple steps of metal loadings without decomposition of the MOF.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000284975100025 Publication Date 2010-11-12
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 194 Open Access
Notes Esteem 026019 Approved Most recent IF: 9.466; 2010 IF: 6.400
Call Number UA @ lucian @ c:irua:95530 Serial 208
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Author Barnabé, A.; Millange, F.; Maignan, A.; Hervieu, M.; Raveau, B.; Van Tendeloo, G.; Laffez, P.
Title Barium-based manganites Ln1-xBaxMnO3 with Ln = {Pr, La}: phase transitions and magnetoresistance properties Type A1 Journal article
Year 1998 Publication Chem. mater. Abbreviated Journal (down) Chem Mater
Volume 10 Issue Pages 252-259
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000071624400037 Publication Date 2002-07-26
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 48 Open Access
Notes Approved Most recent IF: 9.466; 1998 IF: 3.359
Call Number UA @ lucian @ c:irua:25689 Serial 220
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Author Li, Y.; Yang, X.-Y.; Tian, G.; Vantomme, A.; Yu, J.; Van Tendeloo, G.; Su, B.-L.
Title Chemistry of trimethyl aluminum: a spontaneous route to thermally stable 3D crystalline macroporous alumina foams with a hierarchy of pore sizes Type A1 Journal article
Year 2010 Publication Chemistry of materials Abbreviated Journal (down) Chem Mater
Volume 22 Issue 10 Pages 3251-3258
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A simple and spontaneous one-pot self-formation procedure that is easy to scale up has been developed based on the chemistry of trimethylaluminum (TMA), leading to thermally stable macroporous crystalline alumina with a very unique and unprecedented three-dimensional (3D) hierarchical pore structure consisting of well-defined wormlike mesopores. TMA is the precursor of both product and porogene (viz, two working functions within the same molecule (2 in 1)). The materials obtained have been intensively characterized by powder X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), N2 adsorption−desorption, and mercury porosimetry. The open cagelike macrocavities are self-constructed by mesoporous nanorods (diameter of ca. 40−70 nm), which are themselves formed by a random assembly of fibrous nanoparticles 5−6 nm in size. Optical microscopy (OM) has been used in situ to follow the synthesis procedure, which led to the proposal of the formation mechanism. Methane molecules as porogens, which were instantaneously released because of the fast hydrolysis of the chemical precursor, were the key factor in producing these 3D structures with uniform co-continuous macropores that interconnected directly with the wormlike mesopores. The important characteristic of this procedure is the concurrent formation of a multiscaled porous network. The material exhibits great thermal stability. The hierarchically mesoporous−macroporous Al2O3 obtained is quite attractive for a myriad of applications, from catalysis to biomedicine. The present work illustrates that the one-pot self-formation concept, based on the chemistry of alkyl metals, is a versatile method to design industrially valuable hierarchically porous materials.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000277635000030 Publication Date 2010-04-27
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 38 Open Access
Notes Approved Most recent IF: 9.466; 2010 IF: 6.400
Call Number UA @ lucian @ c:irua:82760 Serial 356
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Author Hadermann, J.; Abakumov, A.M.; Van Rompaey, S.; Mankevich, A.S.; Korsakov, I.E.
Title Comment on ALaMn2O6-y (A = K, Rb): novel ferromagnetic manganites exhibiting negative giant magnetoresistance Type Editorial
Year 2009 Publication Chemistry of materials Abbreviated Journal (down) Chem Mater
Volume 21 Issue 9 Pages 2000-2001
Keywords Editorial; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000265781000036 Publication Date 2009-04-14
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 4 Open Access
Notes Approved Most recent IF: 9.466; 2009 IF: 5.368
Call Number UA @ lucian @ c:irua:77055 Serial 411
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Author Adamson, P.; Hadermann, J.; Smura, C.F.; Rutt, O.J.; Hyett, G.; Free, D.G.; Clarke, S.J.
Title Competing magnetic structures and the evolution of copper ion/vacancy ordering with composition in the manganite oxide chalcogenides Sr2MnO2Cu1.5(S1-xSex)2 Type A1 Journal article
Year 2012 Publication Chemistry of materials Abbreviated Journal (down) Chem Mater
Volume 24 Issue 14 Pages 2802-2816
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The series Sr2MnO2Cu1.5(S1-xSex)(2) (0 <= x <= 1) contains mixed-valent Mn ions (Mn2+/Mn3+) in MnO2 sheets which are separated by copper-deficient antifluorite-type Cu(2-delta)Ch(2) layers with delta similar to 0.5. The compounds crystallize in the structure type first described for Sr2Mn3Sb2O2 and are described in the I4/mmm space group at ambient temperatures. Below about 250 K, ordering between Cu+ ions and tetrahedral vacancies occurs which is long-range and close to complete in the sulfide-containing end member of the series Sr2MnO2Cu1.5S2 but which occurs over shorter length scales as the selenide content increases. The superstructure is an orthorhombic 2 root 2a x root 2a x c expansion in Ibam of the room temperature cell. For x > 0.3 there are no superstructure reflections evident in the X-ray or neutron diffraction patterns, and the I4/mmm description is valid for the average structure at all temperatures. However, in the pure selenide end member, Sr2MnO2Cu1.5Se2, diffuse scattering in electron diffractograms and modulation in high resolution lattice image profiles may arise from short-range Cu/vacancy order. All members of the series exhibit long-range magnetic order. In the sulfide-rich end member and in compounds with x < 0.1 in the formula Sr2MnO2Cu1.5(S1-xSex)(2), which show well developed superstructures due to long-range Cu/vacancy order, the magnetic structure has a (1/4 1/4 0) propagation vector in which ferromagnetic zigzag chains of Mn moments in the MnO2 sheets are coupled antiferromagnetically in an arrangement described as the CE-type magnetic structure and found in many mixed-valent perovskite and Ruddlesden-Popper type oxide manganites. In these cases the magnetic cell is an a x 2b x c expansion of the low temperature Ibam structural cell. For x >= 0.2 in the formula Sr2MnO2Cu1.5(S1-xSex)(2) the magnetic structure has a (0 0 0) propagation vector and is similar to the A-type structure, also commonly adopted by some perovskite-related manganites, in which the Mn moments in the MnO2 sheets are coupled ferromagnetically and long-range antiferromagnetic order results from antiferromagnetic coupling between planes. In the region of the transition between the two different structural and magnetic long-range ordering schemes (0.1 < x < 0.2) the two magnetic structures coexist in the same sample. The evolution of the competition between magnetic ordering schemes and the length scale of the structural order with composition in Sr2MnO2Cu1.5(S1-xSex)(2) suggest that the changes in magnetic and structural order are related consequences of the introduction of chemical disorder.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000306674200024 Publication Date 2012-06-20
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 11 Open Access
Notes Esteem 026019 Approved Most recent IF: 9.466; 2012 IF: 8.238
Call Number UA @ lucian @ c:irua:100839 Serial 435
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Author Hadermann, J.; Abakumov, A.M.; Gillie, L.J.; Martin, C.; Hervieu, M.
Title Coupled cation and charge ordering in the CaMn306 tunnel structure Type A1 Journal article
Year 2006 Publication Chemistry of materials Abbreviated Journal (down) Chem Mater
Volume 18 Issue 23 Pages 5530-5536
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000241808600021 Publication Date 2006-10-15
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 33 Open Access
Notes Iap V-1 Approved Most recent IF: 9.466; 2006 IF: 5.104
Call Number UA @ lucian @ c:irua:61374 Serial 534
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Author Morozov, V.A.; Raskina, M.V.; Lazoryak, B.I.; Meert, K.W.; Korthout, K.; Smet, P.F.; Poelman, D.; Gauquelin, N.; Verbeeck, J.; Abakumov, A.M.; Hadermann, J.;
Title Crystal Structure and Luminescent Properties of R2-xEux(MoO4)(3) (R = Gd, Sm) Red Phosphors Type A1 Journal article
Year 2014 Publication Chemistry of materials Abbreviated Journal (down) Chem Mater
Volume 26 Issue 24 Pages 7124-7136
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The R-2(MoO4)(3) (R = rare earth elements) molybdates doped with Eu3+ cations are interesting red-emitting materials for display and solid-state lighting applications. The structure and luminescent properties of the R2-xEux(MoO4)(3) (R = Gd, Sm) solid solutions have been investigated as a function of chemical composition and preparation conditions. Monoclinic (alpha) and orthorhombic (beta') R2-xEux(MoO4)(3) (R = Gd, Sm; 0 <= x <= 2) modifications were prepared by solid-state reaction, and their structures were investigated using synchrotron powder X-ray diffraction and transmission electron microscopy. The pure orthorhombic beta'-phases could be synthesized only by quenching from high temperature to room temperature for Gd2-xEux(MoO4)(3) in the Eu3+-rich part (x > 1) and for all Sm2-xEux(MoO4)(3) solid solutions. The transformation from the alpha-phase to the beta'-phase results in a notable increase (similar to 24%) of the unit cell volume for all R2-xEux(MoO4)(3) (R = Sm, Gd) solid solutions. The luminescent properties of all R2-xEux(MoO4)(3) (R = Gd, Sm; 0 <= x <= 2) solid solutions were measured, and their optical properties were related to their structural properties. All R2-xEux(MoO4)(3) (R = Gd, Sm; 0 <= x <= 2) phosphors emit intense red light dominated by the D-5(0)-> F-7(2) transition at similar to 616 nm. However, a change in the multiplet splitting is observed when switching from the monoclinic to the orthorhombic structure, as a consequence of the change in coordination polyhedron of the luminescent ion from RO8 to RO7 for the alpha- and beta'-modification, respectively. The Gd2-xEux(MoO4)(3) solid solutions are the most efficient emitters in the range of 0 < x < 1.5, but their emission intensity is comparable to or even significantly lower than that of Sm2-xEux(MoO4)(3) for higher Eu3+ concentrations (1.5 <= x <= 1.75). Electron energy loss spectroscopy (EELS) measurements revealed the influence of the structure and element content on the number and positions of bands in the ultraviolet-visible-infrared regions of the EELS spectrum.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000347139700027 Publication Date 2014-11-27
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 24 Open Access
Notes Fwo G039211n; G004413n; 278510 Vortex ECASJO_; Approved Most recent IF: 9.466; 2014 IF: 8.354
Call Number UA @ lucian @ c:irua:122829UA @ admin @ c:irua:122829 Serial 558
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Author Bune, R.O.; Lobanov, M.V.; Popov, G.; Greenblatt, M.; Botez, C.E.; Stephens, P.W.; Croft, M.; Hadermann, J.; Van Tendeloo, G.
Title Crystal structure and properties of Ru-stoichiometric LaSrMnRuO6 Type A1 Journal article
Year 2006 Publication Chemistry of materials Abbreviated Journal (down) Chem Mater
Volume 18 Issue 10 Pages 2611-2617
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000237593400022 Publication Date 2006-05-09
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 17 Open Access
Notes Approved Most recent IF: 9.466; 2006 IF: 5.104
Call Number UA @ lucian @ c:irua:59441 Serial 563
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Author Hadermann, J.; Abakumov, A.; Van Rompaey, S.; Perkisas, T.; Filinchuk, Y.; Van Tendeloo, G.
Title Crystal structure of a lightweight borohydride from submicrometer crystallites by precession electron diffraction Type A1 Journal article
Year 2012 Publication Chemistry of materials Abbreviated Journal (down) Chem Mater
Volume 24 Issue 17 Pages 3401-3405
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We demonstrate that precession electron diffraction at low-dose conditions can be successfully applied for structure analysis of extremely electron-beam-sensitive materials. Using LiBH4 as a test material, complete structural information, including the location of the H atoms, was obtained from submicrometer-sized crystallites. This demonstrates for the first time that, where conventional transmission electron microscopy techniques fail, quantitative precession electron diffraction can provide structural information from submicrometer particles of such extremely electron-beam-sensitive materials as complex lightweight hydrides. We expect the precession electron diffraction technique to be a useful tool for nanoscale investigations of thermally unstable lightweight hydrogen-storage materials.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000308833400012 Publication Date 2012-08-01
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 17 Open Access
Notes Approved Most recent IF: 9.466; 2012 IF: 8.238
Call Number UA @ lucian @ c:irua:101845 Serial 567
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Author Luhrs, C.C.; Molins, E.; Van Tendeloo, G.; Beltran-Porter, D.; Fuertes, A.
Title Crystal structure of Bi6Sr8-xCa3+xO22(-0.5\leq x\leq1.7): a mixed valence bismuth oxide related to perovskite Type A1 Journal article
Year 1998 Publication Chemistry of materials Abbreviated Journal (down) Chem Mater
Volume 10 Issue 7 Pages 1875-1881
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The crystal structure of BiSr8-xCa3+xO22 has been determined by single-crystal X-ray diffraction. This phase is the same as Bi9Sr11Ca5Oy that was previously studied by several authors as a secondary phase in the Bi-Sr-Ca-Cu-O system and coexists in thermodynamic equilibrium with the superconductors Bi2Sr2CuO6 and Bi2Sr2CaCu2O8 It crystallizes in the monoclinic space group P2(1)/c, with cell parameters a 11.037(3) Angstrom, b = 5.971(2) Angstrom, c = 19.703(7) Angstrom, beta = 101.46(3)degrees Z = 2. The structure was solved by direct methods and full-matrix least-squares refinement. It is built up by perovskite-related blocks of composition [Sr8-xBi2Ca3+xO16] that intergrow with double rows [Bi4O6] running along b. The perovskite blocks are formed by groups of five octahedra that are shifted from each other 3/2 root 2a(p) along [110](p) (a(p) being the parameter of the cubic perovskite subcell) in a zigzag configuration and are aligned with this direction parallel to the one forming an angle of 25" with the c axis. In turn, the perovskite blocks [Sr8-xBi2Ca3+xO16] are shifted from each other 1/2 of both a(p) and root 2a(p) along [100](p) and [110](p), respectively. In the double rows, two trivalent bismuth atoms are placed, forming dimeric anion complexes [Bi2O6].(6-).6- The oxygen atoms around bismuth in these dimers are placed in the vertexes of a distorted trigonal bipyramid, with one vacant position that would be occupied by the lone pairs characteristic for the electronic configuration of Bi(III). The B sites in the perovskite blocks are occupied by pentavalent bismuth atoms and calcium atoms; the remaining Sr and Ca ions occupy the A sites of the perovskite blocks with coordination numbers with oxygen ranging from 10 to 12. The mean valence for Bi is +3.67 [33.3% of Bi(V) and 66.7% of Bi(III)]. The oxygen vacancies are located in the boundaries between domains having the two possible configurations of the perovskite subcell as in the anionic superconductor Bi3BaO5.5. The oxidation of Bi6Sr8-xCa3+xO22 at 650 degrees C allows the complete filling of the oxygen vacancies to form the double perovskite (Sr2-xCax)Bi1.4Ca0.6O6 that shows 92.5% of bismuth in +5 oxidation state. The experimental high-resolution electon microscopy image and the electron diffraction pattern of powder samples along the [010]* zone axis are in good agreement with those calculated from the structural model obtained by single-crystal X-ray diffraction. The material is almost free of defects and the occurrence of planar defects is very exceptional.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000075019300023 Publication Date 2002-07-26
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 6 Open Access
Notes Approved Most recent IF: 9.466; 1998 IF: 3.359
Call Number UA @ lucian @ c:irua:104328 Serial 570
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Author Panin, R.V.; Shpanchenko, R.V.; Mironov, A.V.; Velikodny, Y.A.; Antipov, E.V.; Hadermann, J.; Tarnopolsky, V.A.; Yaroslavtsev, A.B.; Kaul, E.E.; Geibel, C.
Title Crystal structure, polymorphism, and properties of the new vanadyl phosphate Na4VO(PO4)2 Type A1 Journal article
Year 2004 Publication Chemistry of materials Abbreviated Journal (down) Chem Mater
Volume 16 Issue Pages 1048-1055
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000220304100014 Publication Date 2004-03-16
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 11 Open Access
Notes Approved Most recent IF: 9.466; 2004 IF: 4.103
Call Number UA @ lucian @ c:irua:43873 Serial 577
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