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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 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 (down)
Notes Approved Most recent IF: 9.466; 2011 IF: 7.286
Call Number UA @ lucian @ c:irua:93581 Serial 151
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Author Batuk, M.; Turner, S.; Abakumov, A.M.; Batuk, D.; Hadermann, J.; Van Tendeloo, G.
Title Atomic structure of defects in anion-deficient perovskite-based ferrites with a crystallographic shear structure Type A1 Journal article
Year 2014 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 53 Issue 4 Pages 2171-2180
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Crystallographic shear (CS) planes provide a new structure-generation mechanism in the anion-deficient perovskites containing lone-pair cations. Pb2Sr2Bi2Fe6O16, a new n = 6 representative of the AnBnO3n2 homologous series of the perovskite-based ferrites with the CS structure, has been synthesized using the solid-state technique. The structure is built of perovskite blocks with a thickness of four FeO6 octahedra spaced by double columns of FeO5 edge-sharing distorted tetragonal pyramids, forming 1/2[110](101)p CS planes (space group Pnma, a = 5.6690(2) Å, b = 3.9108(1) Å, c = 32.643(1) Å). Pb2Sr2Bi2Fe6O16 features a wealth of microstructural phenomena caused by the flexibility of the CS planes due to the variable ratio and length of the constituting fragments with {101}p and {001}p orientation. This leads to the formation of waves, hairpins, Γ-shaped defects, and inclusions of the hitherto unknown layered anion-deficient perovskites Bi2(Sr,Pb)Fe3O8.5 and Bi3(Sr,Pb)Fe4O11.5. Using a combination of diffraction, imaging, and spectroscopic transmission electron microscopy techniques this complex microstructure was fully characterized, including direct determination of positions, chemical composition, and coordination number of individual atomic species. The complex defect structure makes these perovskites particularly similar to the CS structures in ReO3-type oxides. The flexibility of the CS planes appears to be a specific feature of the Sr-based system, related to the geometric match between the SrO perovskite layers and the {100}p segments of the CS planes.
Address
Corporate Author Thesis
Publisher Place of Publication Easton, Pa Editor
Language Wos 000332144100039 Publication Date 2014-01-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue 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 (down)
Notes Countatoms; FWO Approved Most recent IF: 4.857; 2014 IF: 4.762
Call Number UA @ lucian @ c:irua:113507 Serial 198
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Author Marikutsa, A.; Krivetskiy, V.; Yashina, L.; Rumyantseva, M.; Konstantinova, E.; Ponzoni, A.; Comini, E.; Abakumov, A.; Gaskov, A.
Title Catalytic impact of RuOx clusters to high ammonia sensitivity of tin dioxide Type A1 Journal article
Year 2012 Publication Sensors and actuators : B : chemical T2 – 25th Eurosensors Conference, SEP 04-07, 2011, Athens, GREECE Abbreviated Journal Sensor Actuat B-Chem
Volume 175 Issue Pages 186-193
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A comparative study of NH3-sensing performance of blank and modified nanocrystal line SnO2 was performed. Tin dioxide modified by ruthenium displayed the highest ammonia sensitivity with a maximum signal at 200 degrees C. The modifier was shown by XPS and EPR to occur in a mixed valence state of oxidized ruthenium distributed between the surface and bulk of tin dioxide nanocrystals. RuOx clustering on SnO2 surface was detected by means of electron microscopy assisted EDX-mapping. The effect of RuOx on tin dioxide interaction with ammonia was studied by temperature-programmed NH3 desorption, simultaneous Kelvin probe and DC-resistance measurements, EPR spectroscopy and analyses of the gas-solid interaction products. The modifier was shown to promote the materials reactivity to NH3 due to the catalytic activity of RuOx. The interaction with ammonia resulted in dipoles formation on the oxide surface along with reducing the grains net surface charge, established from the electron affinity increase and resistance decrease during NH3 exposure. The RuOx-catalyzed gas-solid interaction was deduced to proceed deeper than in the case of non-modified SnO2 and to yield nitrogen oxides (e.g. NO2), as was suggested by the oxidative character of gaseous products of NH3 interaction with RuOx-modified tin dioxide at 200 degrees C. (C) 2012 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos 000312358700033 Publication Date 2012-06-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0925-4005; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.401 Times cited 20 Open Access (down)
Notes Approved Most recent IF: 5.401; 2012 IF: 3.535
Call Number UA @ lucian @ c:irua:105985 Serial 293
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Author Abakumov, A.M.; Morozov, V.A.; Tsirlin, A.A.; Verbeeck, J.; Hadermann, J.
Title Cation ordering and flexibility of the BO42- tetrahedra in incommensurately modulated CaEu2(BO4)4 (B = Mo, W) scheelites Type A1 Journal article
Year 2014 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 53 Issue 17 Pages 9407-9415
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The factors mediating cation ordering in the scheelite-based molybdates and tungstates are discussed on the basis of the incommensurately modulated crystal structures of the CaEu2(BO4)(4) (B = Mo, W) red phosphors solved from high-resolution synchrotron powder X-ray diffraction data. Monoclinic CaEu2(WO4)(4) adopts a (3 + 1)-dimensionally modulated structure [superspace group I2/b(alpha beta 0)00, a = 5.238 73(1)A, b = 5.266 35(1) A, c = 11.463 19(9) A, gamma = 91.1511(2)degrees, q = 0.56153(6)a* + 0.7708(9)b*, R-F = 0.050, R-p = 0.069], whereas tetragonal CaEu2(MoO4)(4) is (3 + 2)-dimensionally modulated [superspace group I4(1)/ a(alpha beta 0)00(-beta alpha 0)00, a = 5.238 672(7) A, c = 11.548 43(2) A, q(1) = 035331(8)a* + 0.82068(9)b*, q(2) = -0.82068(9)a* + 0.55331(8)b*, R-F = 0.061, R-p = 0.082]. In both cases the modulation arises from the ordering of the Ca/Eu cations and the cation vacancies at the A-sublattice of the parent scheelite ABO(4) structure. The cation ordering is incomplete and better described with harmonic rather than with steplike occupational modulation functions. The structures respond to the variation of the effective charge and cation size at the A-position through the flexible geometry of the MoO42- and WO42- tetrahedra demonstrating an alternation of stretching the B-O bond lengths and bending the O-B-O bond angles. The tendency towards A-site cation ordering in scheelites is rationalized using the difference in ionic radii and concentration of the A-site vacancies as parameters and presented in the form of a structure map.
Address
Corporate Author Thesis
Publisher Place of Publication Easton, Pa Editor
Language Wos 000341229600068 Publication Date 2014-08-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.857 Times cited 48 Open Access (down)
Notes Fwo G039211n Approved Most recent IF: 4.857; 2014 IF: 4.762
Call Number UA @ lucian @ c:irua:119292UA @ admin @ c:irua:119292 Serial 297
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Author Kirsanova, M.A.; Mori, T.; Maruyama, S.; Abakumov, A.M.; Van Tendeloo, G.; Olenev, A.; Shevelkov, A.V.
Title Cationic clathrate of type-III Ge172-xPxTey (y\approx21,5, x\approx2y) : synthesis, crystal structure and thermoelectric properties Type A1 Journal article
Year 2013 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 52 Issue 14 Pages 8272-8279
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A first germanium-based cationic clathrate of type-III, Ge129.3P42.7Te21.53, was synthesized and structurally characterized (space group P42/mnm, a = 19.948(3) Å, c = 10.440(2) Å, Z = 1). In its crystal structure, germanium and phosphorus atoms form three types of polyhedral cages centered with Te atoms. The polyhedra share pentagonal and hexagonal faces to form a 3D framework. Despite the complexity of the crystal structure, the Ge129.3P42.7Te21.53 composition corresponds to the Zintl counting scheme with a good accuracy. Ge129.3P42.7Te21.53 demonstrates semiconducting/insulating behavior of electric resistivity, high positive Seebeck coefficient (500 μV K1 at 300 K), and low thermal conductivity (<0.92 W m1 K1) within the measured temperature range.
Address
Corporate Author Thesis
Publisher Place of Publication Easton, Pa Editor
Language Wos 000322087100052 Publication Date 2013-06-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.857 Times cited 3 Open Access (down)
Notes Countatoms Approved Most recent IF: 4.857; 2013 IF: 4.794
Call Number UA @ lucian @ c:irua:109214 Serial 301
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Author Abakumov, A.M.; Hadermann, J.; Van Tendeloo, G.; Antipov, E.V.
Title Chemistry and structure of anion-deficient perovskites with translational interfaces Type A1 Journal article
Year 2008 Publication Journal of the American Ceramic Society Abbreviated Journal J Am Ceram Soc
Volume 91 Issue 6 Pages 1807-1813
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Columbus, Ohio Editor
Language Wos 000256410700010 Publication Date 2008-04-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0002-7820;1551-2916; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.841 Times cited 39 Open Access (down)
Notes Approved Most recent IF: 2.841; 2008 IF: 2.101
Call Number UA @ lucian @ c:irua:70088 Serial 355
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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 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 (down)
Notes Approved Most recent IF: 9.466; 2009 IF: 5.368
Call Number UA @ lucian @ c:irua:77055 Serial 411
Permanent link to this record
 
 
Author Abakumov, A.M.; Kalyuzhnaya, A.S.; Rozova, M.G.; Antipov, E.V.; Hadermann, J.; Van Tendeloo, G.
Title Compositionally induced phase transition in the Ca2MnGa1-xAlxO5 solid solutions: ordering of tetrahedral chains in brownmillerite structure Type A1 Journal article
Year 2005 Publication Solid state sciences Abbreviated Journal Solid State Sci
Volume 7 Issue 7 Pages 801-811
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000230259500001 Publication Date 2005-04-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1293-2558; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.811 Times cited 38 Open Access (down)
Notes IAP V-1; RFBR 04-03-32785-a. Approved Most recent IF: 1.811; 2005 IF: 1.708
Call Number UA @ lucian @ c:irua:54700 Serial 448
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Author Abakumov, A.M.; d' Hondt, H.; Rossell, M.D.; Tsirlin, A.A.; Gutnikova, O.; Filimonov, D.S.; Schnelle, W.; Rosner, H.; Hadermann, J.; Van Tendeloo, G.; Antipov, E.V.
Title Coupled anion and cation ordering in Sr3RFe4O10.5 (R=Y, Ho, Dy) anion-deficientperovskites Type A1 Journal article
Year 2010 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 183 Issue 12 Pages 2845-2854
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The Sr3RFe4O10.5 (R=Y, Ho, Dy) anion-deficient perovskites were prepared using a solid-state reaction in evacuated sealed silica tubes. Transmission electron microscopy and 57Fe Mössbauer spectroscopy evidenced a complete A-cations and oxygen vacancies ordering. The structure model was further refined by ab initio structure relaxation, based on density functional theory calculations. The compounds crystallize in a tetragonal a≈2√2ap≈11.3 Å, с≈4сp≈16 Å unit cell (ap: parameter of the perovskite subcell) with the P42/mnm space group. Oxygen vacancies reside in the (FeO5/4□3/4) layers, comprising corner-sharing FeO4 tetrahedra and FeO5 tetragonal pyramids, which are sandwiched between the layers of the FeO6 octahedra. Smaller R atoms occupy the 9-fold coordinated position, whereas the 10-fold coordinated positions are occupied by larger Sr atoms. The Fe sublattice is ordered aniferromagnetically up to at least 500 K, while the rare-earth sublattice remains disordered down to 2 K.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000285431100014 Publication Date 2010-10-02
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 8 Open Access (down)
Notes Approved Most recent IF: 2.299; 2010 IF: 2.261
Call Number UA @ lucian @ c:irua:88071 Serial 533
Permanent link to this record
 
 
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 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 (down)
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 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 (down)
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 Shpanchenko, R.V.; Chyornaya, V.V.; Abakumov, A.M.; Antipov, E.V.; Hadermann, J.; Van Tendeloo, G.; Kaul, E.; Geibel, C.; Sheptyakov, D.; Balagurov, A.M.
Title Crystal structure and magnetic properties of novel reduced V(IV)-based oxide Pb2V5O12 Type A1 Journal article
Year 2001 Publication Zeitschrift für anorganische und allgemeine Chemie Abbreviated Journal Z Anorg Allg Chem
Volume 627 Issue Pages 2143-2150
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Leipzig Editor
Language Wos 000171339000023 Publication Date 2002-08-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0044-2313;1521-3749; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.144 Times cited 4 Open Access (down)
Notes Approved Most recent IF: 1.144; 2001 IF: 1.165
Call Number UA @ lucian @ c:irua:36048 Serial 560
Permanent link to this record
 
 
Author Batuk, D.; de Dobbelaere, C.; Tsirlin, A.A.; Abakumov, A.M.; Hardy, A.; van Bael, M.K.; Greenblatt, M.; Hadermann, J.
Title Crystal structure and magnetic properties of the Cr-doped spiral antiferromagnet BiMnFe2O6 Type A1 Journal article
Year 2013 Publication Materials research bulletin Abbreviated Journal Mater Res Bull
Volume 48 Issue 9 Pages 2993-2997
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report the Cr3+ for Mn3+ substitution in the BiMnFe2O6 structure. The BiCrxMn1-xFe2O6 solid solution is obtained by the solution-gel synthesis technique for the x values up to 0.3. The crystal structure investigation using a combination of X-ray powder diffraction and transmission electron microscopy demonstrates that the compounds retain the parent BiMnFe2O6 structure (for x = 0.3, a = 5.02010(6)angstrom, b = 7.06594(7)angstrom, c = 12.6174(1)angstrom, S.G. Pbcm, R-1 = 0.036, R-p = 0.011) with only a slight decrease in the cell parameters associated with the Cr3+ for Mn3+ substitution. Magnetic susceptibility measurements suggest strong similarities in the magnetic behavior of BiCrxMn1-xFe2O6 (x = 0.2; 0.3) and parent BiMnFe2O6. Only T-N slightly decreases upon Cr doping that indicates a very subtle influence of Cr3+ cations on the magnetic properties at the available substitution rates. (C) 2013 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000322354000002 Publication Date 2013-04-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0025-5408; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.446 Times cited 3 Open Access (down)
Notes Fwo Approved Most recent IF: 2.446; 2013 IF: 1.968
Call Number UA @ lucian @ c:irua:109755 Serial 561
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Author King, G.; Abakumov, A.M.; Hadermann, J.; Alekseeva, A.M.; Rozova, M.G.; Perkisas, T.; Woodward, P.M.; Van Tendeloo, G.; Antipov, E.V.
Title Crystal structure and phase transitions in Sr3WO6 Type A1 Journal article
Year 2010 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 49 Issue 13 Pages 6058-6065
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The crystal structures of the beta and gamma polymorphs of Sr3WO6 and the gamma <->beta phase transition have been investigated using electron diffraction, synchrotron X-ray powder diffraction, and neutron powder diffraction. The gamma-Sr3WO6 polymorph is stable above T-c approximate to 470 K and adopts a monoclinically distorted double perovskite A(2)BB'O-6= Sr2SrWO6 structure (space group Cc, a = 10.2363(1)angstrom, b= 17.9007(1)angstrom, c= 11.9717(1)angstrom, beta=125.585(1)degrees at T= 1373 K, Z=12, corresponding to a = a(p)+1/2b(p) – 1/2c(p), b =3/2b(p) + 3/2c(p), c =-b(p) + c(p), a(p),b(p), c(p), lattice vectors of the parent Fm (3) over barm double perovskite structure). Upon cooling it undergoes a continuous phase transition into the triclinically distorted beta-Sr3WO6 phase (space group Cl, a = 10.09497(3)angstrom, b = 17.64748(5)angstrom, c = 11.81400(3)angstrom, alpha = 89.5470(2)degrees, beta= 125.4529(2)degrees, gamma =90.2889(2)degrees at T= 300 K). Both crystal structures of Sr3WO6 belong to a family of double perovskites with broken corner sharing connectivity of the octahedral framework. A remarkable feature of the gamma-Sr3WO6 structure is a non-cooperative rotation of the WO6 octahedra. One third of the WO6 octahedra are rotated by 45 about either the bp or the cp axis of the parent double perovskite structure. As a result, the WO6 octahedra do not share corners but instead share edges with the coordination polyhedra of the Sr cations at the B positions increasing their coordination number from 6 to 7 or 8. The crystal structure of the beta-phase is very close to the structure of the gamma-phase; decreasing symmetry upon the gamma ->beta transformation occurs because of unequal octahedral rotation angles about the bp and cp axes and increasing distortions of the WO6 octahedra.
Address
Corporate Author Thesis
Publisher Place of Publication Easton, Pa Editor
Language Wos 000279211500036 Publication Date 2010-06-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.857 Times cited 18 Open Access (down)
Notes Approved Most recent IF: 4.857; 2010 IF: 4.326
Call Number UA @ lucian @ c:irua:83877 Serial 562
Permanent link to this record
 
 
Author Panin, R.V.; Khasanova, N.R.; Abakumov, A.M.; Schnelle, W.; Hadermann, J.; Antipov, E.V.
Title Crystal structure and properties of the Na1-xRu2O4 phase Type A1 Journal article
Year 2006 Publication Russian chemical bulletin Abbreviated Journal Russ Chem B+
Volume 55 Issue 10 Pages 1717-1722
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000245091400003 Publication Date 2007-03-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1066-5285;1573-9171; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 0.529 Times cited 5 Open Access (down)
Notes Approved Most recent IF: 0.529; 2006 IF: 0.505
Call Number UA @ lucian @ c:irua:63810 Serial 566
Permanent link to this record
 
 
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 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 (down)
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 Abakumov, A.M.; King, G.; Laurinavichute, V.K.; Rozova, M.G.; Woodward, P.M.; Antipov, E.V.
Title The crystal structure of \alpha-K3AIF6: elpasolites and double perovskites with broken corner-sharing connectivity of the octahedral framework Type A1 Journal article
Year 2009 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 48 Issue 19 Pages 9336-9344
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The crystal structure of α-K3AlF6 was solved and refined from a combination of powder X-ray and neutron diffraction data (a = 18.8385(3)Å, c = 33.9644(6)Å, S.G. I41/a, Z = 80, RP(X-ray) = 0.037, RP(neutron) = 0.053). The crystal structure is of the A2BB′X6 elpasolite type with the a = b ≈ ae√5, c = 4ae superstructure (ae, parameter of the elpasolite subcell) and rock-salt-type ordering of the K and Al cations over the B and B′ positions, respectively. The remarkable feature of α-K3AlF6 is a rotation of 2/5 of the AlF6 octahedra by π/4 around one of the crystal axes of the elpasolite subcell, coinciding with the 4-fold symmetry axes of the AlF6 octahedra. The rotation of the AlF6 octahedra replaces the corner-sharing between the K and Al polyhedra by edge-sharing, resulting in an increase of coordination numbers of the K cations at the B positions up to 7 and 8. Due to significant deformations of the K polyhedra, the corner-sharing connectivity of the octahedral elpasolite framework is broken and the rotations of the AlF6 octahedra do not have a cooperative character. Elpasolites and double perovskites with similar structural organization are discussed. The difference in ionic radii of the B and B′ cations as well as the tolerance factor are proposed to be the parameters governing the formation of elpasolites and double perovskites with broken corner-sharing connectivity of the octahedral framework.
Address
Corporate Author Thesis
Publisher Place of Publication Easton, Pa Editor
Language Wos 000270091000039 Publication Date 2009-09-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.857 Times cited 20 Open Access (down)
Notes Approved Most recent IF: 4.857; 2009 IF: 4.657
Call Number UA @ lucian @ c:irua:79733 Serial 568
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Author Abakumov, A.M.; Van Tendeloo, G.; Scheglov, A.A.; Shpanchenko, R.V.; Antipov, E.V.
Title The crystal structure of Ba8Ta6NiO24: cation ordering in hexagonal perovskites Type A1 Journal article
Year 1996 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 125 Issue Pages 102-107
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos A1996VB31300015 Publication Date 2002-10-07
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 2.133 Times cited 38 Open Access (down)
Notes Approved no
Call Number UA @ lucian @ c:irua:16868 Serial 569
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Author Abakumov, A.M.; Shpanchenko, R.V.; Antipov, E.V.; Lebedev, O.I.; Van Tendeloo, G.
Title The crystal structure of Ca3ReO6 Type A1 Journal article
Year 1997 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 131 Issue Pages 305-309
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos A1997XQ33000014 Publication Date 0000-00-00
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 10 Open Access (down)
Notes Approved Most recent IF: 2.299; 1997 IF: 1.486
Call Number UA @ lucian @ c:irua:21442 Serial 571
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Author Nikolaev, I.V.; d' Hondt, H.; Abakumov, A.M.; Hadermann, J.; Balagurov, A.M.; Bobrikov, I.A.; Sheptyakov, D.V.; Pomjakushin, V.Y.; Pokholok, K.V.; Filimonov, D.S.; Van Tendeloo, G.; Antipov, E.V.
Title Crystal structure, phase transition, and magnetic ordering in perovskitelike Pb2-xBaxFe2O5 solid solutions Type A1 Journal article
Year 2008 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 78 Issue 2 Pages 024426,1-12
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000258190200085 Publication Date 2008-07-24
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 29 Open Access (down)
Notes Iap Vi Approved Most recent IF: 3.836; 2008 IF: 3.322
Call Number UA @ lucian @ c:irua:70580 Serial 576
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Author Abakumov, A.M.; Hadermann, J.; Bals, S.; Nikolaev, I.V.; Antipov, E.V.; Van Tendeloo, G.
Title Crystallographic shear structures as a route to anion-deficient perovskites Type A1 Journal article
Year 2006 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit
Volume 45 Issue 40 Pages 6697-6700
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000241474500022 Publication Date 2006-09-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-7851;1521-3773; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 11.994 Times cited 62 Open Access (down)
Notes Approved Most recent IF: 11.994; 2006 IF: 10.232
Call Number UA @ lucian @ c:irua:61689 Serial 589
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Author Monico, L.; Janssens, K.; Miliani, C.; Brunetti, B.G.; Vagnini, M.; Vanmeert, F.; Falkenberg, G.; Abakumov, A.; Lu, Y.; Tian, H.; Verbeeck, J.; Radepont, M.; Cotte, M.; Hendriks, E.; Geldof, M.; van der Loeff, L.; Salvant, J.; Menu, M.;
Title Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods : 3 : synthesis, characterization, and detection of different crystal forms of the chrome yellow pigment Type A1 Journal article
Year 2013 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 85 Issue 2 Pages 860-867
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The painter, Vincent van Gogh, and some of his contemporaries frequently made use of the pigment chrome yellow that is known to show a tendency toward darkening. This pigment may correspond to various chemical compounds such as PbCrO4 and PbCr1-xSxO4, that may each be present in various crystallographic forms with different tendencies toward degradation. Investigations by X-ray diffraction (XRD), mid-Fourier Transform infrared (FTIR), and Raman instruments (benchtop and portable) and synchrotron radiation-based micro-XRD and X-ray absorption near edge structure spectroscopy performed on oil-paint models, prepared with in-house synthesized PbCrO4 and PbCr1-xSxO4, permitted us to characterize the spectroscopic features of the various forms. On the basis of these results, an extended study has been carried out on historic paint tubes and on embedded paint microsamples taken from yellow-orange/pale yellow areas of 12 Van Gogh paintings, demonstrating that Van Gogh effectively made use of different chrome yellow types. This conclusion was also confirmed by in situ mid-FTIR investigations on Van Goghs Portrait of Gauguin (Van Gogh Museum, Amsterdam).
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000313668400031 Publication Date 2012-10-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700;1520-6882; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.32 Times cited 79 Open Access (down)
Notes Goa; Fwo Approved Most recent IF: 6.32; 2013 IF: 5.825
Call Number UA @ lucian @ c:irua:108707UA @ admin @ c:irua:108707 Serial 631
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Author Reynaud, M.; Rousse, G.; Abakumov, A.M.; Sougrati, M.T.; Van Tendeloo, G.; Chotard, J.-N.; Tarascon, J.-M.
Title Design of new electrode materials for Li-ion and Na-ion batteries from the bloedite mineral Na2Mg(SO4)2\cdot4H2O Type A1 Journal article
Year 2014 Publication Journal of materials chemistry A : materials for energy and sustainability Abbreviated Journal J Mater Chem A
Volume 2 Issue 8 Pages 2671-2680
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Mineralogy offers a large database to search for Li- or Na-based compounds having suitable structural features for acting as electrode materials, LiFePO4 being one example. Here we further explore this avenue and report on the electrochemical properties of the bloedite type compounds Na2M(SO4)(2)center dot 4H(2)O (M = Mg, Fe, Co, Ni, Zn) and their dehydrated phases Na2M(SO4)(2) (M = Fe, Co), whose structures have been solved via complementary synchrotron X-ray diffraction, neutron powder diffraction and transmission electron microscopy. Among these compounds, the hydrated and anhydrous iron-based phases show electrochemical activity with the reversible release/uptake of 1 Na+ or 1 Li+ at high voltages of similar to 3.3 V vs. Na+/Na-0 and similar to 3.6 V vs. Li+/Li-0, respectively. Although the reversible capacities remain lower than 100 mA h g(-1), we hope this work will stress further the importance of mineralogy as a source of inspiration for designing eco-efficient electrode materials.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000331247500031 Publication Date 2013-11-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7488;2050-7496; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.867 Times cited 56 Open Access (down)
Notes Approved Most recent IF: 8.867; 2014 IF: 7.443
Call Number UA @ lucian @ c:irua:115807 Serial 659
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Author Rossell, M.D.; Abakumov, A.M.; Ramasse, Q.M.; Erni, R.
Title Direct evidence of stacking disorder in the mixed ionic-electronic conductor Sr4Fe6O12+\delta Type A1 Journal article
Year 2013 Publication ACS nano Abbreviated Journal Acs Nano
Volume 7 Issue 4 Pages 3078-3085
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Determining the structure-to-property relationship of materials becomes particularly challenging when the material under investigation is dominated by defects and structural disorder. Knowledge on the exact atomic arrangement at the defective structure is required to understand its influence on the functional properties. However, standard diffraction techniques deliver structural information that is averaged over many unit cells. In particular, information about defects and order-disorder phenomena is contained in the coherent diffuse scattering intensity which often is difficult to uniquely interpret. Thus, the examination of the local disorder in materials requires a direct method to study their structure on the atomic level with chemical sensitivity. Using aberration-corrected scanning transmission electron microscopy in combination with atomic-resolution electron energy-loss spectroscopy, we show that the controversial structural arrangement of the Fe2O2+delta layers in the mixed ionic-electronic conducting Sr4Fe6O12+delta perovskite can be unambiguously resolved. Our results provide direct experimental evidence for the presence of a nanomixture of “ordered” and “disordered” domains in an epitaxial Sr4Fe6O12+delta thin film. The most favorable arrangement is the disordered structure and is interpreted as a randomly occurring but well-defined local shift of the Fe-O chains in the Fe2O2+delta layers. By analyzing the electron energy-loss near-edge structure of the different building blocks in the Sr4Fe6O12+delta unit cell we find that the mobile holes in this mixed ionic-electronic conducting oxide are highly localized in the Fe2O2+delta layers, which are responsible for the oxide-ion conductivity. A possible link between disorder and oxygen-ion transport along the Fe2O2+delta layers is proposed by arguing that the disorder can effectively break the oxygen diffusion pathways.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000318143300021 Publication Date 2013-03-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited 4 Open Access (down)
Notes Approved Most recent IF: 13.942; 2013 IF: 12.033
Call Number UA @ lucian @ c:irua:108476 Serial 713
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Author Hadermann, J.; Abakumov, A.M.; Tsirlin, A.A.; Filonenko, V.P.; Gonnissen, J.; Tan, H.; Verbeeck, J.; Gemmi, M.; Antipov, E.V.; Rosner, H.
Title Direct space structure solution from precession electron diffraction data: resolving heavy and light scatterers in Pb13Mn9O25 Type A1 Journal article
Year 2010 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 110 Issue 7 Pages 881-890
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The crystal structure of a novel compound Pb13Mn9O25 has been determined through a direct space structure solution with a Monte-Carlo-based global optimization using precession electron diffraction data (a=14.177(3) Å, c=3.9320(7) Å, SG P4/m, RF=0.239) and compositional information obtained from energy dispersive X-ray analysis and electron energy loss spectroscopy. This allowed to obtain a reliable structural model even despite the simultaneous presence of both heavy (Pb) and light (O) scattering elements and to validate the accuracy of the electron diffraction-based structure refinement. This provides an important benchmark for further studies of complex structural problems with electron diffraction techniques. Pb13Mn9O25 has an anion- and cation-deficient perovskite-based structure with the A-positions filled by the Pb atoms and 9/13 of the B positions filled by the Mn atoms in an ordered manner. MnO6 octahedra and MnO5 tetragonal pyramids form a network by sharing common corners. Tunnels are formed in the network due to an ordered arrangement of vacancies at the B-sublattice. These tunnels provide sufficient space for localization of the lone 6s2 electron pairs of the Pb2+ cations, suggested as the driving force for the structural difference between Pb13Mn9O25 and the manganites of alkali-earth elements with similar compositions.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000280050900023 Publication Date 2010-04-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited 24 Open Access (down)
Notes Fwo; Bof; Esteem Approved Most recent IF: 2.843; 2010 IF: 2.063
Call Number UA @ lucian @ c:irua:84085UA @ admin @ c:irua:84085 Serial 721
Permanent link to this record
 
 
Author Gou, H.; Dubrovinskaia, N.; Bykova, E.; Tsirlin, A.A.; Kasinathan, D.; Schnelle, W.; Richter, A.; Merlini, M.; Hanfland, M.; Abakumov, A.M.; Batuk, D.; Van Tendeloo, G.; Nakajima, Y.; Kolmogorov, A.N.; Dubrovinsky, L.;
Title Discovery of a superhard iron tetraboride superconductor Type A1 Journal article
Year 2013 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 111 Issue 15 Pages 157002-157005
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Single crystals of novel orthorhombic (space group Pnnm) iron tetraboride FeB4 were synthesized at pressures above 8 GPa and high temperatures. Magnetic susceptibility and heat capacity measurements demonstrate bulk superconductivity below 2.9 K. The putative isotope effect on the superconducting critical temperature and the analysis of specific heat data indicate that the superconductivity in FeB4 is likely phonon mediated, which is rare for Fe-based superconductors. The discovered iron tetraboride is highly incompressible and has the nanoindentation hardness of 62(5) GPa; thus, it opens a new class of highly desirable materials combining advanced mechanical properties and superconductivity.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000325371500011 Publication Date 2013-10-09
Series Editor Series Title 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 127 Open Access (down)
Notes Countatoms Approved Most recent IF: 8.462; 2013 IF: 7.728
Call Number UA @ lucian @ c:irua:110820 Serial 729
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Author Batuk, D.; Batuk, M.; Abakumov, A.M.; Tsirlin, A.A.; McCammon, C.M.; Dubrovinsky, L.; Hadermann, J.
Title Effect of lone-electron-pair cations on the orientation of crystallographic shear planes in anion-deficient perovskites Type A1 Journal article
Year 2013 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 52 Issue 17 Pages 10009-10020
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Factors affecting the structure and orientation of the crystallographic shear (CS) planes in anion-deficient perovskites are investigated using the (Pb1−zSrz)1−xFe1+xO3−y perovskites as a model system. The orientation of the CS planes in the system varies unevenly with z. A comparison of the structures with different CS planes revels that the orientation of the CS planes is governed mainly by the stereochemical activity of the lone-electron-pair cations inside the perovskite blocks.
Address
Corporate Author Thesis
Publisher Place of Publication Easton, Pa Editor
Language Wos 000326129000037 Publication Date 2013-08-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.857 Times cited 11 Open Access (down)
Notes Fwo Approved Most recent IF: 4.857; 2013 IF: 4.794
Call Number UA @ lucian @ c:irua:111394 Serial 822
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Author Abakumov, A.; Rozova, M.; Shpanchenko, R.; Kovba, M.; Putilin, S.; Antipov, E.; Lebedev, O.; Van Tendeloo, G.; Kopnin, E.; Karpinski, J.
Title Effects of fluorination on the structure and superconducting properties of Y2Ba4Cu7O14+ phases Type A1 Journal article
Year 1998 Publication Physica: C : superconductivity Abbreviated Journal Physica C
Volume 301 Issue Pages 155-164
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000074516500005 Publication Date 2002-07-25
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 9 Open Access (down)
Notes Approved Most recent IF: 1.404; 1998 IF: 1.086
Call Number UA @ lucian @ c:irua:25663 Serial 862
Permanent link to this record
 
 
Author Meert, K.W.; Morozov, V.A.; Abakumov, A.M.; Hadermann, J.; Poelman, D.; Smet, P.F.
Title Energy transfer in Eu3+ doped scheelites : use as thermographic phosphor Type A1 Journal article
Year 2014 Publication Optics express Abbreviated Journal Opt Express
Volume 22 Issue 9 Pages A961-A972
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract In this paper the luminescence of the scheelite-based CaGd2(1-x)Eu2x(WO4)4 solid solutions is investigated as a function of the Eu content and temperature. All phosphors show intense red luminescence due to the 5D0 7F2 transition in Eu3+, along with other transitions from the 5D1 and 5D0 excited states. For high Eu3+ concentrations the intensity ratio of the emission originating from the 5D1 and 5D0 levels has a non-conventional temperature dependence, which could be explained by a phonon-assisted cross-relaxation process. It is demonstrated that this intensity ratio can be used as a measure of temperature with high spatial resolution, allowing the use of these scheelites as thermographic phosphor. The main disadvantage of many thermographic phosphors, a decreasing signal for increasing temperature, is absent.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000335905300037 Publication Date 2014-04-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1094-4087; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.307 Times cited 47 Open Access (down)
Notes Approved Most recent IF: 3.307; 2014 IF: 3.488
Call Number UA @ lucian @ c:irua:117067 Serial 1044
Permanent link to this record
 
 
Author Bourgeois, J.; Hervieu, M.; Poienar, M.; Abakumov, A.M.; Elkaïm, E.; Sougrati, M.T.; Porcher, F.; Damay, F.; Rouquette, J.; Van Tendeloo, G.; Maignan, A.; Haines, J.; Martin, C.;
Title Evidence of oxygen-dependent modulation in LuFe2O4 Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 85 Issue 6 Pages 064102-064120,10
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A polycrystalline sample of LuFe2O4 has been investigated by means of powder synchrotron x-ray and neutron diffraction and transmission electron microscopy (TEM), along with Mössbauer spectroscopy and transport and magnetic properties. A monoclinic distortion is unambiguously evidenced, and the crystal structure is refined in the monoclinic C2/m space group [aM = 5.9563(1) Å, bM = 3.4372(1) Å, cM = 8.6431(1) Å, β = 103.24(1)°]. Along with the previously reported modulations distinctive of the charge-ordering (CO) of the iron species, a new type of incommensurate order is observed, characterized by a vector q⃗1 = α1a⃗M* + γ1c⃗M* (with α1 ≅ 0.55, γ1 ≅ 0.13). In situ heating TEM observations from 300 to 773 K confirm that the satellites associated with q⃗1 vanish completely, only at a temperature significantly higher than the CO temperature. This incommensurate modulation has a displacive character and corresponds primarily to a transverse displacive modulation wave of the Lu cations position, as revealed by the high resolution, high angle annular dark field scanning TEM images and in agreement with synchrotron data refinements. Analyses of vacuum-annealed samples converge toward the hypothesis of a new ordering mechanism, associated with a tiny oxygen deviation from the O4 stoichiometry.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000299896900003 Publication Date 2012-02-06
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 24 Open Access (down)
Notes Hercules Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:95042 Serial 1095
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