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Author Tsirlin, A.A.; Nath, R.; Abakumov, A.M.; Shpanchenko, R.V.; Geibel, C.; Rosner, H. url  doi
openurl 
  Title Frustrated square lattice with spatial anisotropy: crystal structure and magnetic properties of PbZnVO(PO4)2 Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 81 Issue 17 Pages 174424,1-174424,13  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Crystal structure and magnetic properties of the layered vanadium phosphate PbZnVO(PO4)2 are studied using x-ray powder diffraction, magnetization and specific-heat measurements, as well as band-structure calculations. The compound resembles AA′VO(PO4)2 vanadium phosphates and fits to the extended frustrated square-lattice model with the couplings J1, J1′ between nearest neighbors and J2, J2′ between next-nearest neighbors. The temperature dependence of the magnetization yields estimates of averaged nearest-neighbor and next-nearest-neighbor couplings, J̅ 1≃−5.2 K and J̅ 2≃10.0 K, respectively. The effective frustration ratio α=J̅ 2/J̅ 1 amounts to −1.9 and suggests columnar antiferromagnetic ordering in PbZnVO(PO4)2. Specific-heat data support the estimates of J̅ 1 and J̅ 2 and indicate a likely magnetic ordering transition at 3.9 K. However, the averaged couplings underestimate the saturation field, thus pointing to the spatial anisotropy of the nearest-neighbor interactions. Band-structure calculations confirm the identification of ferromagnetic J1, J1′ and antiferromagnetic J2, J2′ in PbZnVO(PO4)2 and yield (J1′−J1)≃1.1 K in excellent agreement with the experimental value of 1.1 K, deduced from the difference between the expected and experimentally measured saturation fields. Based on the comparison of layered vanadium phosphates with different metal cations, we show that a moderate spatial anisotropy of the frustrated square lattice has minor influence on the thermodynamic properties of the model. We discuss relevant geometrical parameters, controlling the exchange interactions in these compounds and propose a strategy for further design of strongly frustrated square-lattice materials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000278141600082 Publication Date 2010-05-25  
  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 27 Open Access  
  Notes Approved (down) Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:83384 Serial 1294  
Permanent link to this record
 

 
Author Tsirlin, A.A.; Abakumov, A.M.; Van Tendeloo, G.; Rosner, H. url  doi
openurl 
  Title Interplay of atomic displacement in the quantum magnet (CuCI)LaNb2O7 Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 82 Issue 5 Pages 054107,1-054107,12  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract We report on the crystal structure of the quantum magnet CuClLaNb2O7 that was controversially described with respect to its structural organization and magnetic behavior. Using high-resolution synchrotron powder x-ray diffraction, electron diffraction, transmission electron microscopy, and band-structure calculations, we solve the room-temperature structure of this compound -CuClLaNb2O7 and find two high-temperature polymorphs. The -CuClLaNb2O7 phase, stable above 640 K, is tetragonal with asub=3.889 Å, csub =11.738 Å, and the space group P4/mmm. In the -CuClLaNb2O7 structure, the Cu and Cl atoms are randomly displaced from the special positions along the 100 directions. The phase asub2asubcsub, space group Pbmm and the phase 2asub2asubcsub, space group Pbam are stable between 640 K and 500 K and below 500 K, respectively. The structural changes at 500 and 640 K are identified as order-disorder phase transitions. The displacement of the Cl atoms is frozen upon the → transformation while a cooperative tilting of the NbO6 octahedra in the phase further eliminates the disorder of the Cu atoms. The low-temperature -CuClLaNb2O7 structure thus combines the two types of the atomic displacements that interfere due to the bonding between the Cu atoms and the apical oxygens of the NbO6 octahedra. The precise structural information resolves the controversy between the previous computation-based models and provides the long-sought input for understanding CuClLaNb2O7 and related compounds with unusual magnetic properties.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000280849400001 Publication Date 2010-08-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 13 Open Access  
  Notes Approved (down) Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:83991 Serial 1706  
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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. doi  openurl
  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  
  Notes Iap Vi Approved (down) Most recent IF: 3.836; 2008 IF: 3.322  
  Call Number UA @ lucian @ c:irua:70580 Serial 576  
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Author Lobanov, M.V.; Balagurov, A.M.; Pomjakushin, V.J.; Fischer, P.; Gutmann, M.; Abakumov, A.M.; D'yachenko, O.G.; Antipov, E.V.; Lebedev, O.I.; Van Tendeloo, G. doi  openurl
  Title Structural and magnetic properties of the colossal magnetoresistance perovskite La0.85Ca0.15MnO3 Type A1 Journal article
  Year 2000 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 61 Issue 13 Pages 8941-8949  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000086597400059 Publication Date 2002-07-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 47 Open Access  
  Notes Approved (down) Most recent IF: 3.836; 2000 IF: NA  
  Call Number UA @ lucian @ c:irua:54735 Serial 3197  
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Author Tsirlin, A.A.; Rousochatzakis, I.; Filimonov, D.; Batuk, D.; Frontzek, M.; Abakumov, A.M. url  doi
openurl 
  Title Spin-reorientation transitions in the Cairo pentagonal magnet Bi4Fe5O13F Type A1 Journal article
  Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 96 Issue 9 Pages 094420  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract We show that interlayer spins play a dual role in the Cairo pentagonal magnet Bi4Fe5O13F, on one hand mediating the three-dimensional magnetic order, and on the other driving spin-reorientation transitions both within and between the planes. The corresponding sequence of magnetic orders unraveled by neutron diffraction and Mossbauer spectroscopy features two orthogonal magnetic structures described by opposite local vector chiralities, and an intermediate, partly disordered phase with nearly collinear spins. A similar collinear phase has been predicted theoretically to be stabilized by quantum fluctuations, but Bi4Fe5O13F is very far from the relevant parameter regime. While the observed in-plane reorientation cannot be explained by any standard frustration mechanism, our ab initio band-structure calculations reveal strong single-ion anisotropy of the interlayer Fe3+ spins that turns out to be instrumental in controlling the local vector chirality and the associated interlayer order.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000411161700002 Publication Date 2017-09-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 7 Open Access OpenAccess  
  Notes We are grateful to J.-M. Perez-Mato and Dmitry Khalyavin for valuable discussions on the magnetic structures and symmetries. D.F. and A.A. are grateful to the Russian Science Foundation (Grant No. 14-13-00680) for support. A.T. was supported by the Federal Ministry for Education and Research through the Sofja Kovalevskaya Award of the Alexander von Humboldt Foundation. This work is based on experiments performed at the Swiss spallation neutron source SINQ, Paul Scherrer Institut, Villigen, Switzerland. Approved (down) Most recent IF: 3.836  
  Call Number EMAT @ emat @c:irua:146748 Serial 4774  
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Author Meert, K.W.; Morozov, V.A.; Abakumov, A.M.; Hadermann, J.; Poelman, D.; Smet, P.F. url  doi
openurl 
  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  
  Notes Approved (down) Most recent IF: 3.307; 2014 IF: 3.488  
  Call Number UA @ lucian @ c:irua:117067 Serial 1044  
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Author McCalla, E.; Prakash, A.S.; Berg, E.; Saubanere, M.; Abakumov, A.M.; Foix, D.; Klobes, B.; Sougrati, M.T.; Rousse, G.; Lepoivre, F.; Mariyappan, S.; Doublet, M.L.; Gonbeau, D.; Novak, P.; Van Tendeloo, G.; Hermann, R.P.; Tarascon, J.M.; pdf  doi
openurl 
  Title Reversible Li-intercalation through oxygen reactivity in Li-rich Li-Fe-Te oxide materials Type A1 Journal article
  Year 2015 Publication Journal of the electrochemical society Abbreviated Journal J Electrochem Soc  
  Volume 162 Issue 162 Pages A1341-A1351  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Lithium-rich oxides are a promising class of positive electrode materials for next generation lithium-ion batteries, and oxygen plays a prominent role during electrochemical cycling either by forming peroxo-like species and/or by irreversibly forming oxygen gas during first charge. Here, we present Li-Fe-Te-O materials which show a tremendous amount of oxygen gas release. This oxygen release accounts for nearly all the capacity during the first charge and results in vacancies as seen by transmission electron microscopy. There is no oxidation of either metal during charge but significant changes in their environments. These changes are particularly extreme for tellurium. XRD and neutron powder diffraction both show limited Changes during cycling and no appreciable change in lattice parameters. A density functional theory study of this material is performed and demonstrates that the holes created on some of the oxygen atoms upon oxidation are partially stabilized through the formation of shorter O-O bonds, i.e. (O-2)(n-) species which on further delithiation show a spontaneous O-2 de-coordination from the cationic network and migration to the now empty lithium layer. The rate limiting step during charge is undoubtedly the diffusion of oxygen either out along the lithium layer or via columns of oxygen atoms. (C) 2015 The Electrochemical Society. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000355643700030 Publication Date 2015-04-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0013-4651;1945-7111; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.259 Times cited 23 Open Access  
  Notes Approved (down) Most recent IF: 3.259; 2015 IF: 3.266  
  Call Number c:irua:126445 Serial 2903  
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Author Vassiliev, S.Y.; Laurinavichute, V.K.; Abakumov, A.M.; Govorov, V.A.; Bendovskii, E.B.; Turner, S.; Filatov, A.Y.; Tarasovskii, V.P.; Borzenko, A.G.; Alekseeva, A.M.; Antipov, E.V. pdf  doi
openurl 
  Title Microstructural aspects of the degradation behavior of SnO2-based anodes for aluminum electrolysis Type A1 Journal article
  Year 2010 Publication Journal of the electrochemical society Abbreviated Journal J Electrochem Soc  
  Volume 157 Issue 5 Pages C178-C186  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The performance of SnO2 ceramic anodes doped with copper and antimony oxides was examined in cryolite alumina melts under anodic polarization at different cryolite ratios, temperatures, times, and current densities. The corroded part consists of a narrow strong corrosion zone at the anode surface with damage of the intergrain contacts and a large increase in porosity, a wider moderate corrosion zone with a smaller porosity increase, and a Cu depletion zone, where the ceramic retains its initial microstructure and a slight porosity increase occurs due to the removal of the Cu-rich inclusions. Mechanical destruction of the anode was never observed in the 10100 h tests. A microstructural model of the ceramic was suggested, consisting of grains with an Sb-doped SnO2 grain core surrounded by an ~200 to 500 nm grain shell where SnO2 was simultaneously doped with Sb and Mn+ (M=Cu2+,Fe3+,Al3+). The grains were separated by a few nanometers thick Cu-enriched grain boundaries. Different secondary charge carrier (holes) concentrations and electric conductivities in the grain core and grain shell result in a higher current density at the intergrain regions that leads to their profound degradation, especially in the low temperature acidic melt.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000276555300037 Publication Date 2010-04-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0013-4651; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.259 Times cited 3 Open Access  
  Notes Approved (down) Most recent IF: 3.259; 2010 IF: 2.427  
  Call Number UA @ lucian @ c:irua:82260 Serial 2040  
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Author Zakharova, E.Y.; Kazakov, S.M.; Isaeva, A.A.; Abakumov, A.M.; Van Tendeloo, G.; Kuznetsov, A.N. doi  openurl
  Title Pd5InSe and Pd8In2Se : new metal-rich homological selenides with 2D palladium-indium fragments : synthesis, structure and bonding Type A1 Journal article
  Year 2014 Publication Journal of alloys and compounds Abbreviated Journal J Alloy Compd  
  Volume 589 Issue Pages 48-55  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Two new metal-rich palladium-indium selenides, Pd5InSe and Pd8In2Se, were synthesized using a high-temperature ampoule technique. Their crystal structures were determined from Rietveld analysis of powder diffraction data, supported by energy-dispersive X-ray spectroscopy and selected area electron diffraction. Both compounds crystallize in tetragonal system with P4/mmm space group (Pd5InSe: a = 4.0290(3) angstrom, c = 6.9858(5) angstrom, Z = 1; Pd8In2Se: a = 4.0045(4) angstrom, c = 10.952(1) angstrom, Z = 1). The first compound belongs to the Pd5TlAs structure type, while the second one – to a new structure type. Main structural units in both selenides are indium-centered [Pd12In] cuboctahedra of the tetragonally distorted Cu3Au type, single-and double-stacked along the c axis in Pd5InSe and Pd8In2Se, respectively, alternating with [Pd8Se] rectangular prisms. DFT electronic structure calculations predict both compounds to be 3D metallic conductors and Pauli-like paramagnets. According to the bonding analysis based on the electron localization function topology, both compounds feature multi-centered palladium-indium interactions in their heterometallic fragments. (C) 2013 Elsevier B. V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000330181400008 Publication Date 2013-12-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0925-8388; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.133 Times cited 12 Open Access  
  Notes Approved (down) Most recent IF: 3.133; 2014 IF: 2.999  
  Call Number UA @ lucian @ c:irua:114840 Serial 3552  
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Author Zhukova, A.A.; Rumyantseva, M.N.; Zaytsev, V.B.; Zaytseva, A.V.; Abakumov, A.M.; Gaskov, A.M. doi  openurl
  Title Pd nanoparticles on SnO2(Sb) whiskers : aggregation and reactivity in CO detection Type A1 Journal article
  Year 2013 Publication Journal of alloys and compounds Abbreviated Journal J Alloy Compd  
  Volume 565 Issue Pages 6-10  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Single crystal antimony-doped SnO2 whiskers have been synthesized by in situ doping process in horizontal flow reactor. The produced whiskers were modified with 0.1, 0.2, 0.5, 1 or 2 wt.% Pd. The processes of Pd particles growth and aggregation are described on the base of AFM and STEM data. Depending on the content of introduced Pd precursor, the various mechanisms (Volmer-Weber or Stranski-Krastanov) of Pd nanoparticles growth realize. The dependence of sensor signal to CO on Pd concentration has non-monotonous character determined by the size of Pd nanoparticles and their aggregation degree. The best sensor signal toward CO was observed for whiskers decorated with 0.1 wt.% Pd. This concentration corresponds to the presence of individual 3-5 nm Pd nanoparticles on the surface of the whiskers. (C) 2013 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000317815300002 Publication Date 2013-03-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0925-8388; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.133 Times cited Open Access  
  Notes Approved (down) Most recent IF: 3.133; 2013 IF: 2.726  
  Call Number UA @ lucian @ c:irua:108424 Serial 2566  
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Author Bramnik, K.G.; Abakumov, A.M.; Shpanchenko, R.V.; Antipov, E.V.; Van Tendeloo, G. doi  openurl
  Title Synthesis and structure of Ln4Re6-xO19 (Ln=Ce, Pr, Nd) complex oxides Type A1 Journal article
  Year 1998 Publication Journal of alloys and compounds Abbreviated Journal J Alloy Compd  
  Volume 278 Issue Pages 98-102  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000075799200020 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0925-8388; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.133 Times cited 8 Open Access  
  Notes Approved (down) Most recent IF: 3.133; 1998 IF: 0.880  
  Call Number UA @ lucian @ c:irua:25677 Serial 3444  
Permanent link to this record
 

 
Author Batuk, D.; Batuk, M.; Morozov, V.A.; Meert, K.W.; Smet, P.F.; Poelman, D.; Abakumov, A.M.; Hadermann, J. pdf  url
doi  openurl
  Title Effect of cation vacancies on the crystal structure and luminescent properties of Ca(0.85-1.5x)Gd(x)Eu(0.1)_(0.05+0.5x)WO(4) (0<x<0.567) scheelite-based red phosphors Type A1 Journal article
  Year 2017 Publication Journal of alloys and compounds Abbreviated Journal J Alloy Compd  
  Volume 706 Issue 706 Pages 358-369  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract The Ca0.85-1.5xGdxEu0.1_0.05-0.5xWO4 (0 < x < 0.567) series of cation-deficient scheelites is investigated to unveil the influence of the cation vacancies on the crystal structure and luminescent properties. The concentration of the vacancies is varied by the heterovalent substitution of Gd3+ for Ca2+, keeping the concentration of the Eu3+ luminescent centers constant in all compounds of the series. The crystal structure of the materials is studied using a combination of transmission electron microscopy and synchrotron X-ray powder diffraction. At low vacancy concentration (x = 0.1, 0.2), cations and cation vacancies are randomly distributed in the structure, and the materials preserve the I41/a symmetry of the parent scheelite structure [x = 0.1: a = 5.25151(1) Å, c = 11.39479(2) Å; x = 0.2: a = 5.25042(1) Å, c = 11.41335(2) Å]. At higher concentration, the cation-vacancy ordering gives rise to incommensurately modulated structures. The x = 0.3 structure has a (3 + 2)D tetragonal symmetry [superspace group I41/a(a,b,0)00(-b,a,0)00, a = 5.24700(1) Å, c = 11.45514(3) Å, q1 = 0.51637(14)a* + 0.80761(13)b*, q2 = -0.80761a* + 0.51637b*]. At x = 0.4, the scheelite basic cell undergoes a monoclinic distortion with the formation of the (3 + 1)D structure [superspace group I2/b(a,b,0)00, a = 5.23757(1) Å, b = 5.25035(1) Å, c = 11.45750(2) Å, g = 90.5120(2) o, q = 0.54206(8)a* + 0.79330(8)b*]. In both structures, the antiphase Ca and (Gd,Eu) occupancy modulations indicate that the ordering between the A cations and vacancies also induces partial Ca/(Gd,Eu) cation ordering. Further increase of the Gd3þ content up to x = 0.567 leads to the formation of a monoclinic phase (space group C2/c) with the Eu2/3WO4-type structure. Despite the difference in the cation-vacancy ordering patterns, all materials in the series demonstrate very similar quantum efficiency and luminescence decay lifetimes. However, the difference in the local coordination environment of the A cation species noticeably affects the line width and the multiplet splitting of the 4f6-4f6 transitions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000397997300045 Publication Date 2017-02-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0925-8388 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.133 Times cited 2 Open Access OpenAccess  
  Notes This research was supported by FWO (Flanders Research Foundation, project G039211N). V.A.M. is grateful for financial support of the Russian Foundation for Basic Research (Grant 15-03-07741).We are grateful to the ESRF for granting the beamtime at the ID22 beamline and to Andy Fitch for the support during the experiment. Approved (down) Most recent IF: 3.133  
  Call Number EMAT @ emat @ c:irua:142367 Serial 4581  
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Author Kolchina, L. M.; Lyskov, N.V.; Kuznetsov, A.N.; Kazakov, S.M.; Galin, M.Z.; Meledin, A.; Abakumov, A.M.; Bredikhin, S.I.; Mazo, G.N.; Antipov, E.V. pdf  url
doi  openurl
  Title Evaluation of Ce-doped Pr2CuO4for potential application as a cathode material for solid oxide fuel cells Type A1 Journal article
  Year 2016 Publication RSC advances Abbreviated Journal Rsc Adv  
  Volume 6 Issue 6 Pages 101029-101037  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Pr2−xCexCuO4 (x = 0.05; 0.1; 0.15) samples were synthesized and systematically characterized towards application as a cathode material for solid oxide fuel cells (SOFCs). High-temperature electrical conductivity, thermal expansion, and electrocatalytic activity in the oxygen reduction reaction (ORR) were examined. The electrical conductivity of Pr2−xCexCuO4 oxides demonstrates semiconducting behavior up to 900 °C. Small Ce-doping (2.5 at%) allows an increase in electrical conductivity from 100 to 130 S cm−1 in air at 500–800 °C. DFT calculations revealed that the density of states directly below the Fermi level, comprised mainly of Cu 3d and O 2p states, is significantly affected by atoms in rare earth positions, which might give an indication of a correlation between calculated electronic structures and measured conducting properties. Ce-doping in Pr2−xCexCuO4 slightly increases TEC from 11.9 × 10−6 K−1 for x = 0 to 14.2 × 10−6 K−1 for x = 0.15. Substitution of 2.5% of Pr atoms in Pr2CuO4 by Ce is effective to enhance the electrochemical performance of the material as a SOFC cathode in the ORR (ASR of Pr1.95Ce0.05CuO4 electrode applied on Ce0.9Gd0.1O1.95 electrolyte is 0.39 Ω cm2 at 750 °C in air). The peak power density achieved for the electrolyte-supported fuel cell with the Pr1.95Ce0.05CuO4 cathode is 150 mW cm−2 at 800 °C  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000387427700044 Publication Date 2016-10-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2046-2069 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.108 Times cited 7 Open Access  
  Notes his work was partially supported by Russian Foundation for Basic Research (grant no. 153820247), Skolkovo Institute of Science and Technology (Center of electrochemical energy), and MSUdevelopment Program up to 2020. K.L.M. is grateful to Haldor Topsøe A/S for the financial support. Approved (down) Most recent IF: 3.108  
  Call Number EMAT @ emat @ c:irua:136441 Serial 4296  
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Author Ulu Okudur, F.; D'Haen, J.; Vranken, T.; De Sloovere, D.; Verheijen, M.; Karakulina, O.M.; Abakumov, A.M.; Hadermann, J.; Van Bael, M.K.; Hardy, A. pdf  url
doi  openurl
  Title Ti surface doping of LiNi0.5Mn1.5O4−δpositive electrodes for lithium ion batteries Type A1 Journal article
  Year 2018 Publication RSC advances Abbreviated Journal Rsc Adv  
  Volume 8 Issue 13 Pages 7287-7300  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The particle surface of LiNi0.5Mn1.5O4−δ (LNMO), a Li-ion battery cathode material, has been modified by Ti cation doping through a hydrolysis–condensation reaction followed by annealing in oxygen. The effect of different annealing temperatures (500–850 °C) on the Ti distribution and electrochemical performance of the surface modified LNMO was investigated. Ti cations diffuse from the preformed amorphous ‘TiOx’ layer into the LNMO surface during annealing at 500 °C. This results in a 2–4 nm thick Ti-rich spinel surface having lower Mn and Ni content compared to the core of the LNMO particles, which was observed with scanning transmission electron microscopy coupled with compositional EDX mapping. An increase in the annealing temperature promotes the formation of a Ti bulk doped LiNi(0.5−w)Mn(1.5+w)−tTitO4 phase and Ti-rich LiNi0.5Mn1.5−yTiyO4 segregates above 750 °C. Fourier-transform infrared spectrometry indicates increasing Ni–Mn ordering with annealing temperature, for both bare and surface modified LNMO. Ti surface modified LNMO annealed at 500 °C shows a superior cyclic stability, coulombic efficiency and rate performance compared to bare LNMO annealed at 500 °C when cycled at 3.4–4.9 V vs. Li/Li+. The improvements are probably due to suppressed Ni and Mn dissolution with Ti surface doping.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000425508900064 Publication Date 2018-02-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2046-2069 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.108 Times cited 9 Open Access OpenAccess  
  Notes This research is supported by the Research Foundation Flanders (FWO Vlaanderen, grant number G040116N). This project receives the support of the European Union, the European Regional Development Fund ERDF, Flanders Innovation & Entrepreneurship and the Province of Limburg (project 936). Greet Cuyvers and Gilles Bonneux (UHasselt) are acknowledged for the ICP-AES sample preparation and measurements. Vera Meynen and Karen Leyssens (Antwerp University, Belgium) are acknowledged for the BET measurements. Special thanks to Bart Ruttens (UHasselt) for XRD measurements and discussions on the refinements. Approved (down) Most recent IF: 3.108  
  Call Number EMAT @ emat @c:irua:149513 Serial 4905  
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Author Ovsyannikov, S.V.; Bykov, M.; Bykova, E.; Kozlenko, D.P.; Tsirlin, A.A.; Karkin, A.E.; Shchennikov, V.V.; Kichanov, S.E.; Gou, H.; Abakumov, A.M.; Egoavil, R.; Verbeeck, J.; McCammon, C.; Dyadkin, V.; Chernyshov, D.; van Smaalen, S.; Dubrovinsky, L.S. pdf  url
doi  openurl
  Title Charge-ordering transition in iron oxide Fe4O5 involving competing dimer and trimer formation Type A1 Journal article
  Year 2016 Publication Nature chemistry Abbreviated Journal Nat Chem  
  Volume 8 Issue 8 Pages 501-508  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Phase transitions that occur in materials, driven, for instance, by changes in temperature or pressure, can dramatically change the materials' properties. Discovering new types of transitions and understanding their mechanisms is important not only from a fundamental perspective, but also for practical applications. Here we investigate a recently discovered Fe4O5 that adopts an orthorhombic CaFe3O5-type crystal structure that features linear chains of Fe ions. On cooling below approximately 150 K, Fe4O5 undergoes an unusual charge-ordering transition that involves competing dimeric and trimeric ordering within the chains of Fe ions. This transition is concurrent with a significant increase in electrical resistivity. Magnetic-susceptibility measurements and neutron diffraction establish the formation of a collinear antiferromagnetic order above room temperature and a spin canting at 85 K that gives rise to spontaneous magnetization. We discuss possible mechanisms of this transition and compare it with the trimeronic charge ordering observed in magnetite below the Verwey transition temperature.  
  Address Bayerisches Geoinstitut, Universitat Bayreuth, Universitatsstrasse 30, D-95447, Bayreuth, Germany  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Wos 000374534100019 Publication Date 2016-04-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1755-4330 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 25.87 Times cited 51 Open Access  
  Notes S.V.O. acknowledges the financial support of the Deutsche Forschungsgemeinschaft (DFG) under project OV-110/1-3. A.E.K. and V.V.S. acknowledge the support of the Russian Foundation for Basic Research (Project 14–02–00622a). H.G. acknowledges the support from the Alexander von Humboldt (AvH) Foundation and the National Natural Science Foundation of China (No. 51201148). A.M.A., R.E. and J.V. acknowledge financial support from the European Commission (EC) under the Seventh Framework Programme (FP7) under a contract for an Integrated Infrastructure Initiative, Reference No. 312483- ESTEEM2. R.E. acknowledges support from the EC under FP7 Grant No. 246102 IFOX. A.M.A. acknowledges funding from the Russian Science Foundation (Grant No. 14-13- 00680). A.A.T. acknowledges funding and from the Federal Ministry for Education and Research through the Sofja Kovalevkaya Award of the AvH Foundation. Funding from the Fund for Scientific Research Flanders under FWO Project G.0044.13N is acknowledged. M.B. and S.v.S. acknowledge support from the DFG under Project Sm55/15-2. We acknowledge the European Synchrotron Radiation Facility for the provision of synchrotron radiation facilities.; esteem2jra2; esteem2jra3 Approved (down) Most recent IF: 25.87  
  Call Number c:irua:133593 c:irua:133593UA @ admin @ c:irua:133593 Serial 4068  
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Author O'Sullivan, M.; Hadermann, J.; Dyer, M.S.; Turner, S.; Alaria, J.; Manning, T.D.; Abakumov, A.M.; Claridge, J.B.; Rosseinsky, M.J. pdf  doi
openurl 
  Title Interface control by chemical and dimensional matching in an oxide heterostructure Type A1 Journal article
  Year 2016 Publication Nature chemistry Abbreviated Journal Nat Chem  
  Volume 8 Issue 8 Pages 347-353  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Interfaces between different materials underpin both new scientific phenomena, such as the emergent behaviour at oxide interfaces, and key technologies, such as that of the transistor. Control of the interfaces between materials with the same crystal structures but different chemical compositions is possible in many materials classes, but less progress has been made for oxide materials with different crystal structures. We show that dynamical self-organization during growth can create a coherent interface between the perovskite and fluorite oxide structures, which are based on different structural motifs, if an appropriate choice of cations is made to enable this restructuring. The integration of calculation with experimental observation reveals that the interface differs from both the bulk components and identifies the chemical bonding requirements to connect distinct oxide structures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000372505500013 Publication Date 2016-02-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1755-4330; 1755-4349 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 25.87 Times cited 28 Open Access  
  Notes Approved (down) Most recent IF: 25.87  
  Call Number UA @ lucian @ c:irua:133189 Serial 4199  
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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. pdf  doi
openurl 
  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  
  Notes Fwo; Bof; Esteem Approved (down) Most recent IF: 2.843; 2010 IF: 2.063  
  Call Number UA @ lucian @ c:irua:84085UA @ admin @ c:irua:84085 Serial 721  
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Author Abakumov, A.M.; Hadermann, J.; Van Tendeloo, G.; Antipov, E.V. pdf  doi
openurl 
  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  
  Notes Approved (down) Most recent IF: 2.841; 2008 IF: 2.101  
  Call Number UA @ lucian @ c:irua:70088 Serial 355  
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Author Batuk, D.; de Dobbelaere, C.; Tsirlin, A.A.; Abakumov, A.M.; Hardy, A.; van Bael, M.K.; Greenblatt, M.; Hadermann, J. pdf  doi
openurl 
  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  
  Notes Fwo Approved (down) Most recent IF: 2.446; 2013 IF: 1.968  
  Call Number UA @ lucian @ c:irua:109755 Serial 561  
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Author Batuk, M.; Tyablikov, O.A.; Tsirlin, A.A.; Kazakov, S.M.; Rozova, M.G.; Pokholok, K.V.; Filimonov, D.S.; Antipov, E.V.; Abakumov, A.M.; Hadermann, J. pdf  doi
openurl 
  Title Structure and magnetic properties of a new anion-deficient perovskite Pb2Ba2BiFe4ScO13 with crystallographic shear structure Type A1 Journal article
  Year 2013 Publication Materials research bulletin Abbreviated Journal Mater Res Bull  
  Volume 48 Issue 9 Pages 3459-3465  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Pb2Ba2BiFe4ScO13, a new n = 5 member of the oxygen-deficient perovskite-based A(n)B(n)O(3n-2) homologous series, was synthesized using a solid-state method. The crystal structure of Pb2Ba2BiFe4ScO13 was investigated by a combination of synchrotron X-ray powder diffraction, electron diffraction, high-angle annular dark-field scanning transmission electron microscopy and Mossbauer spectroscopy. At 900 K, it crystallizes in the Ammm space group with the unit cell parameters a = 5.8459(1) angstrom, b = 4.0426(1) angstrom, and c=27.3435(1) angstrom. In the Pb2Ba2BiFe4ScO13 structure, quasi-two-dimensional perovskite blocks are periodically interleaved with 1/2[1 1 0] ((1) over bar 0 1)(p) crystallographic shear (CS) planes. At the CS planes, the corner-sharing FeO6 octahedra are transformed into chains of edge-sharing FeO5 distorted tetragonal pyramids. B-positions of the perovskite blocks between the CS planes are jointly occupied by Fe3+ and Sc3+. The chains of the FeO5 pyramids and (Fe,Sc)O-6 octahedra delimit six-sided tunnels that are occupied by double columns of cations with a lone electron pair (Pb2+). The remaining A-cations (Bi3+, Ba2+) occupy positions in the perovskite block. According to the magnetic susceptibility measurements, Pb2Ba2BiFe4ScO13 is antiferromagnetically ordered below T-N approximate to 350 K. (C) 2013 Elsevier Ltd. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000322354000076 Publication Date 2013-05-17  
  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 2 Open Access  
  Notes Approved (down) Most recent IF: 2.446; 2013 IF: 1.968  
  Call Number UA @ lucian @ c:irua:109756 Serial 3282  
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Author Prituzhalov, V.A.; Abakumov, A.M.; Ardashnikova, E.I.; Dolgikh, V.A.; Van Tendeloo, G. doi  openurl
  Title :Ba2.1Bi0.9(O, F)6.8-\delta: a new ordered anion-excess fluorite Type A1 Journal article
  Year 2007 Publication Materials research bulletin Abbreviated Journal Mater Res Bull  
  Volume 42 Issue 5 Pages 861-869  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000245842600010 Publication Date 2006-10-05  
  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 4 Open Access  
  Notes Approved (down) Most recent IF: 2.446; 2007 IF: 1.484  
  Call Number UA @ lucian @ c:irua:64724 Serial 3515  
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Author Serov, T.V.; Dombrovski, E.N.; Ardashnikova, E.I.; Dolgikh, V.A.; el Omari, M.; el Omari, M.; Abaouz, A.; Senegas, J.; Chaban, N.G.; Abakumov, A.M.; Van Tendeloo, G. pdf  doi
openurl 
  Title Fluorite-like phases in the BaF2-BiF3-Bi2O3 system-synthesis, conductivity and defect clustering Type A1 Journal article
  Year 2005 Publication Materials research bulletin Abbreviated Journal Mater Res Bull  
  Volume 40 Issue 5 Pages 821-830  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000229376500012 Publication Date 2005-03-01  
  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 4 Open Access  
  Notes Iap V-1 Approved (down) Most recent IF: 2.446; 2005 IF: 1.380  
  Call Number UA @ lucian @ c:irua:54838 Serial 1240  
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Author Rozova, M.G.; Grigoriev, V.V.; Tyablikov, O.A.; Filimonov, D.S.; Zakharov, K.V.; Volkova, O.S.; Vasiliev, A.N.; Antipov, E.V.; Abakumov, A.M. pdf  doi
openurl 
  Title Doping of Bi4Fe5O13F with pentagonal Cairo lattice with Cr and Mn: Synthesis, structure and magnetic properties Type A1 Journal article
  Year 2017 Publication Materials research bulletin Abbreviated Journal Mater Res Bull  
  Volume 87 Issue 87 Pages 54-60  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The substitution of Cr3+ and Mn3+ for Fe3+ in the Bi4Fe6O13F oxyfluoride featuring the magnetically frustrated pentagonal Cairo lattice is reported. Bi4Fe4.1Cr0.9O13F and BiFe4.2Mn0.8O13F have been prepared using a solid state reaction in inert atmosphere. Their crystal structures were studied with transmission electron microscopy, powder X-ray diffraction and Fe-57 Mossbauer spectroscopy (S.G. P4(2)/mbc, a = 8.27836(2)angstrom, c = 18.00330(9) angstrom, R-F = 0.031 (Bi4Fe4.1Cr0.9O13F)), a= 8.29535(3)angstrom, c= 18.0060(1)angstrom, R-F = 0.027 (Bi4Fe4.1Cr0.9O13F)). The structures are formed by infinite rutile-like chains of the edge sharing BO6 octahedra (B transition metal cations) linked by the Fe2O7 groups of two corner-sharing tetrahedra. The"voids in thus formed framework are occupied by the Bi4F tetrahedra. The Fe-57 Mossbauer spectroscopy reveals that Cr3+ and Mn3+ replace Fe3+. exclusively at the octahedral positions. The Mn- and Cr-doped compounds demonstrate antiferromagnetic ordering below T-N =165 K and 120 K, respectively. (C) 2016 Elsevier Ltd. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000392681800009 Publication Date 2016-11-17  
  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 1 Open Access Not_Open_Access  
  Notes ; The work has been supported by the Russian Science Foundation (grant 14-13-00680). ; Approved (down) Most recent IF: 2.446  
  Call Number UA @ lucian @ c:irua:141535 Serial 4498  
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Author Isaeva, A.A.; Makarevich, O.N.; Kutznetsov, A.N.; Doert, T.; Abakumov, A.M.; Van Tendeloo, G. doi  openurl
  Title Mixed tellurides Ni3-xGaTe2 (0\leq x\leq0.65): crystal and electronic structures, properties, and nickel deficiency effects on vacancy ordering Type A1 Journal article
  Year 2010 Publication European journal of inorganic chemistry Abbreviated Journal Eur J Inorg Chem  
  Volume Issue 9 Pages 1395-1404  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The Ni3-xGaTe2 series of compounds (0 x 0.65) was synthesized by a high-temperature ceramic technique at 750 °C. Crystal structures of three compounds in the series were determined by X-ray powder diffraction: Ni2.98(1)GaTe2 (RI = 0.042, Rp = 0.023, Rwp = 0.035), Ni2.79(1)GaTe2 (RI = 0.053, Rp = 0.028, Rwp = 0.039), Ni2.58(1)GaTe2 (RI = 0.081, Rp = 0.037, Rwp = 0.056); the structures were verified by electron diffraction and, for the former compound, high-resolution electron microscopy. The compounds crystallize in a hexagonal lattice with P63/mmc, and the structures can be regarded as a hexagonal close-packed array with a -Ga-Te-Te- stacking sequence. The octahedral and trigonal bipyramidal voids in the hcp structure are selectively filled with Ni atoms to form one entirely occupied and two partially occupied sites, thus allowing variations in the nickel content in the series of compounds Ni3-xGaTe2 (0 x 0.65). A superstructure with asup = 2asub (P63/mmc) has been identified for Ni3-xGaTe2 (0.5 x 0.65) by electron diffraction. Real-space, high-resolution images confirm an ordering of Ni atoms and vacancies inthe ab plane. Quantum-chemical calculations performed forNi3-xGaTe2 (x = 0, 0.25, 0.75, 1) suggest anisotropic metallic conductivity and Pauli paramagnetic behavior that are experimentally confirmed for Ni3GaTe2.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Weinheim Editor  
  Language Wos 000276370300009 Publication Date 2010-02-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1434-1948;1099-0682; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.444 Times cited 8 Open Access  
  Notes Approved (down) Most recent IF: 2.444; 2010 IF: 2.910  
  Call Number UA @ lucian @ c:irua:82266 Serial 2090  
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Author Fedotov, S.S.; Aksyonov, D.A.; Samarin, A.S.; Karakulina, O.M.; Hadermann, J.; Stevenson, K.J.; Khasanova, N.R.; Abakumov, A.M.; Antipov, E., V pdf  url
doi  openurl
  Title Tuning the crystal structure of A2CoPO4F(A=Li,Na) fluoride-phosphates : a new layered polymorph of LiNaCoPO4F Type A1 Journal article
  Year 2019 Publication European journal of inorganic chemistry Abbreviated Journal Eur J Inorg Chem  
  Volume 2019 Issue 2019 Pages 4365-4372  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Co-containing fluoride-phosphates are of interest in sense of delivering high electrode potentials and attractive specific energy values as positive electrode materials for rechargeable batteries. In this paper we report on a new Co-based fluoride-phosphate, LiNaCoPO4F, with a layered structure (2D), which was Rietveld-refined based on X-ray powder diffraction data [P2(1)/c, a = 6.83881(4) angstrom, b = 11.23323(5) angstrom, c = 5.07654(2) angstrom, beta = 90.3517(5) degrees, V = 389.982(3) angstrom(3)] and validated by electron diffraction and high-resolution scanning transmission electron microscopy. The differential scanning calorimetry measurements revealed that 2D-LiNaCoPO4F forms in a narrow temperature range of 520-530 degrees C and irreversibly converts to the known 3D-LiNaCoPO4F modification (Pnma) above 530 degrees C. The non-carbon-coated 2D-LiNaCoPO4F shows reversible electrochemical activity in Li-ion cell in the potential range of 3.0-4.9 V vs. Li/Li+ with an average potential of approximate to 4.5 V and in Na-ion cell in the range of 3.0-4.5 V vs. Na/Na+ exhibiting a plateau profile centered around 4.2 V, in agreement with the calculated potentials by density functional theory. The energy barriers for both Li+ and Na+ migration in 2D-LiNaCoPO4F amount to 0.15 eV along the [001] direction rendering 2D-LiNaCoPO4F as a viable electrode material for high-power Li- and Na-ion rechargeable batteries. The discovery and stabilization of the 2D-LiNaCoPO4F polymorph indicates that temperature influence on the synthesis of A(2)MPO(4)F fluoride-phosphates needs more careful examination with perspective to unveil new structures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000484135500001 Publication Date 2019-08-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1434-1948 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.444 Times cited Open Access  
  Notes ; This work is supported by the Russian Science Foundation (grant 17-73-30006). The authors greatly thank Dr. D. Rupasov for TG-DSC experiments, B. D. Shmykov and A. I. Manoilov for assistance with sample preparation, the Skoltech Center for Energy Science and Technology and the Moscow State University Program of Development up to 2020. J. Hadermann and O. M. Karakulina acknowledge support from the FWO under grant G040116N. ; Approved (down) Most recent IF: 2.444  
  Call Number UA @ admin @ c:irua:162857 Serial 5403  
Permanent link to this record
 

 
Author Lomakov, M.V.; Istomin, S.Y.; Abakumov, A.M.; Van Tendeloo, G.; Antipov, E.V. doi  openurl
  Title Synthesis and characterization of oxygen-deficient oxides BaCo1-xYxO3-y' x = 0.15, 0.25 and 0.33, with the perovskite structure Type A1 Journal article
  Year 2008 Publication Solid state ionics Abbreviated Journal Solid State Ionics  
  Volume 179 Issue 33/34 Pages 1885-1889  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Oxygen-deficient complex cobalt oxides BaCo1 − xYxO3 − y, = 0.15, 0.25 and 0.33, with a cubic perovskite structure have been synthesized in air at 1100 °C using a citrate route. Cation composition of the compounds was confirmed by energy-dispersed X-ray (EDX) microanalysis while oxygen content was determined by iodometric titration. An electron diffraction (ED) study of the x = 0.25 and 0.33 compositions show the presence of a diffuse intensity, indicating possible short-range ordering of the B cations. It was found that the treatment of BaCo0.75Y0.25O2.55 in a humid atmosphere leads to the absorption of water vapour at the first stage. Oxygen permeation studies of the ceramic membranes of BaCo0.75Y0.25O2.55 and BaCo0.67Y0.33O2.55 with variable thickness showed high oxygen fluxes of 0.170.32 µmol/cm2/s at 950 °C.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000261870800009 Publication Date 2008-06-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0167-2738; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.354 Times cited 9 Open Access  
  Notes Approved (down) Most recent IF: 2.354; 2008 IF: 2.425  
  Call Number UA @ lucian @ c:irua:75905 Serial 3415  
Permanent link to this record
 

 
Author Batuk, M.; Batuk, D.; Abakumov, A.M.; Hadermann, J. pdf  doi
openurl 
  Title Pb5Fe3TiO11Cl : a rare example of Ti(IV) in a square pyramidal oxygen coordination Type A1 Journal article
  Year 2014 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem  
  Volume 215 Issue Pages 245-252  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract A new oxychloride Pb5Fe3TiO11Cl has been synthesized using the solid state method. Its crystal and magnetic structure was investigated in the 1.5550 K temperature range using electron diffraction, high angle annular dark field scanning transmission electron microscopy, atomic resolution energy dispersive X-ray spectroscopy, neutron and X-ray powder diffraction. At room temperature Pb5Fe3TiO11Cl crystallizes in the P4/mmm space group with the unit cell parameters a=3.91803(3) Å and c=19.3345(2) Å. Pb5Fe3TiO11Cl is a new n=4 member of the oxychloride perovskite-based homologous series An+1BnO3n−1Cl. The structure is built of truncated Pb3Fe3TiO11 quadruple perovskite blocks separated by CsCl-type Pb2Cl slabs. The perovskite blocks consist of two layers of (Fe,Ti)O6 octahedra sandwiched between two layers of (Fe,Ti)O5 square pyramids. The Ti4+ cations are preferentially located in the octahedral layers, however, the presence of a noticeable amount of Ti4+ in a five-fold coordination environment has been undoubtedly proven using neutron powder diffraction and atomic resolution compositional mapping. Pb5Fe3TiO11Cl is antiferromagnetically ordered below 450(10) K. The ordered Fe magnetic moments at 1.5 K are 4.06(4) μB and 3.86(5) μB on the octahedral and square-pyramidal sites, respectively.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000336891300037 Publication Date 2014-04-12  
  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 4 Open Access  
  Notes Fwo G.0184.09n. Approved (down) Most recent IF: 2.299; 2014 IF: 2.133  
  Call Number UA @ lucian @ c:irua:117066 Serial 3551  
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Author Frolov, D.D.; Kotovshchikov, Y.N.; Morozov, I.V.; Boltalin, A.I.; Fedorova, A.A.; Marikutsa, A.V.; Rumyantseva, M.N.; Gaskov, A.M.; Sadovskaya, E.M.; Abakumov, A.M. pdf  doi
openurl 
  Title Oxygen exchange on nanocrystalline tin dioxide modified by palladium Type A1 Journal article
  Year 2012 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem  
  Volume 186 Issue Pages 1-8  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Temperature-programmed oxygen isotopic exchange study was performed on nanocrystalline tin dioxide-based materials synthesized via sol-gel route and modified by palladium. Such materials are widely used as resistive gas sensors. The experiments were carried out in a flow-reactor up to complete isotopic substitution of oxygen. Substantial rates of isotopic exchange for SnO2 were observed from about 700 K. The distribution of isotopic molecules O-16(2). (OO)-O-16-O-18 and O-18(2) corresponds to simple dioxygen heteroexchange mechanism with single lattice oxygen atom. The modification of SnO2 by Pd introduced multiple heteroexchange mechanism with preliminary O-2 dissociation on the clusters surface. Spill-over of atomic oxygen from Pd to the surface of SnO2 and fast exchange with lattice oxygen result in more than 100% increase of apparent heteroexchange rate. The exchange on SnO2/Pd was shown to be a complex process involving partial deactivation of the catalytic centers at temperature higher than 750 K. (C) 2011 Elsevier Inc. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000299801400001 Publication Date 2011-12-08  
  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 34 Open Access  
  Notes Approved (down) Most recent IF: 2.299; 2012 IF: 2.040  
  Call Number UA @ lucian @ c:irua:96202 Serial 2546  
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Author Napolsky, P.S.; Drozhzhin, O.A.; Istomin, S.Y.; Kazakov, S.M.; Antipov, E.V.; Galeeva, A.V.; Gippius, A.A.; Svensson, G.; Abakumov, A.M.; Van Tendeloo, G. doi  openurl
  Title Structure and high-temperature properties of the (Sr,Ca,Y)(Co,Mn)O3-y perovskites – perspective cathode materials for IT-SOFC Type A1 Journal article
  Year 2012 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem  
  Volume 192 Issue Pages 186-194  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Oxygen deficient perovskites Sr0.75Y0.25Co1-xMnxO3-y, x=0.5 and 0.75, were prepared by using the citrate route at 1373-1573 K for 48 h. The cubic Pm-3m perovskite structure for x=0.5 was confirmed by electron diffraction study and refined using neutron powder diffraction (NPD) data. For x=0.75, the superstructure corresponding to a=root 2 x a(per), b=2 x a(per), c=root 2 x a(per) (a(0)b(-)b(-) tilt system, space group Imma) was revealed by electron diffraction. The solid solution Sr0.75-xCaxY0.25Co0.25Mn0.75O3-y, 0.1 <= x <= 0.6 and compound Ca0.75Y0.25Mn0.85Co0.15O2.92 were prepared in air at 1573 K for 48 h. The crystal structure of Ca0.75Y0.25Mn0.85Co0.15O2.92 was refined using NPD data (S.G. Pnma, a=5.36595(4), b=7.5091(6), c=5.2992(4) angstrom, R-p=0.057, R-wp=0.056, chi(2)=4.26). High-temperature thermal expansion properties of the prepared compounds were studied in air using both dilatometry and high-temperature X-ray powder diffraction data (HTXRPD). They expanding non-linearly at 298-1073 K due to the loss of oxygen at high temperatures. Calculated average thermal expansion coefficients (TECs) for Sr0.75Y0.25Co1-xMnxO3-y, x=0.5, 0.75 and Ca0.75Y0.25Mn0.85Co0.15O2.92(1) are 15.5, 15.1, and 13.8 ppm K-1, respectively. Anisotropy of the thermal expansion along different unit cell axes was observed for Sr0.15Ca0.6Y0.25Co0.25Mn0.75O3-y, and Ca0.75Y0.25Mn0.85Co0.15O2.92. Conductivity of Sr0.75Y0.25Co1-xMnxO3-y, x=0.5 and 0.75 increases with the temperature reaching 110 S/cm for x=0.5 and 44 S/cm for x=0.75 at 1173 K. Samples of Sr0.75-xCaxY0.25Co0.25Mn0.75O3-y, 0.1 <= y <= 0.6 were found to be n-type conductors at room temperature with the similar temperature dependence of the conductivity and demonstrated the increase of the sigma value from similar to 1 to similar to 50 S/cm as the temperature increases from 300 to 1173 K. Their conductivity is described in terms of the small polaron charge transport with the activation energy (E-p) increasing from 340 to 430 meV with an increase of the calcium content from x=0 to x=0.6. (C) 2012 Elsevier Inc. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000307028300030 Publication Date 2012-03-31  
  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 5 Open Access  
  Notes Approved (down) Most recent IF: 2.299; 2012 IF: 2.040  
  Call Number UA @ lucian @ c:irua:101119 Serial 3279  
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Author Korneychik, O.E.; Batuk, M.; Abakumov, A.M.; Hadermann, J.; Rozova, M.G.; Sheptyakov, D.V.; Pokholok, K.V.; Filimonov, D.S.; Antipov, E.V. pdf  doi
openurl 
  Title Pb2.85Ba2.15Fe4SnO13 : a new member of the AnBnO3n-2 anion-deficient perovskite-based homologous series Type A1 Journal article
  Year 2011 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem  
  Volume 184 Issue 12 Pages 3150-3157  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Pb2.85Ba2.15Fe4SnO13, a new n=5 member of the anion-deficient perovskite based AnBnO3n−2 (A=Pb, Ba, B=Fe, Sn) homologous series, was synthesized by the solid state method. The crystal structure of Pb2.85Ba2.15Fe4SnO13 was investigated using a combination of neutron powder diffraction, electron diffraction, high angle annular dark field scanning transmission electron microscopy and Mössbauer spectroscopy. It crystallizes in the Ammm space group with unit cell parameters a=5.7990(1) Å, b=4.04293(7) Å and c=26.9561(5) Å. The Pb2.85Ba2.15Fe4SnO13 structure consists of quasi two-dimensional perovskite blocks separated by 1/2[110](1̄01)p crystallographic shear (CS) planes. The corner-sharing FeO6 octahedra at the CS planes are transformed into edge-sharing FeO5 distorted tetragonal pyramids. The octahedral positions in the perovskite blocks between the CS planes are jointly taken up by Fe and Sn, with a preference of Sn towards the position at the center of the perovskite block. The chains of FeO5 pyramids and (Fe,Sn)O6 octahedra of the perovskite blocks delimit six-sided tunnels at the CS planes occupied by double chains of Pb atoms. The compound is antiferromagnetically ordered below TN=368±15 K.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000297662500003 Publication Date 2011-09-30  
  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 7 Open Access  
  Notes Approved (down) Most recent IF: 2.299; 2011 IF: 2.159  
  Call Number UA @ lucian @ c:irua:94013 Serial 3550  
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