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	Author	Mallick, S.; Zhang, W.; Batuk, M.; Gibbs, A.S.; Hadermann, J.; Halasyamani, P.S.; Hayward, M.A.
	Title	The crystal and defect structures of polar KBiNb₂O₇			Type	A1 Journal article
	Year	2022	Publication	Journal of the Chemical Society : Dalton transactions	Abbreviated Journal	Dalton T
	Volume	51	Issue	5	Pages	1866-1873
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	KBiNb2O7 was prepared from RbBiNb2O7 by a sequence of cation exchange reactions which first convert RbBiNb2O7 to LiBiNb2O7, before KBiNb2O7 is formed by a further K-for-Li cation exchange. A combination of neutron, synchrotron X-ray and electron diffraction data reveal that KBiNb2O7 adopts a polar, layered, perovskite structure (space group A11m) in which the BiNb2O7 layers are stacked in a (0, ½, z) arrangement, with the K+ cations located in half of the available 10-coordinate interlayer cation sites. The inversion symmetry of the phase is broken by a large displacement of the Bi3+ cations parallel to the y-axis. HAADF-STEM images reveal that KBiNb2O7 exhibits frequent stacking faults which convert the (0. ½, z) layer stacking to (½, 0, z) stacking and vice versa, essentially switching the x- and y-axes of the material. By fitting the complex diffraction peak shape of the SXRD data collected from KBiNb2O7 it is estimated that each layer has approximately an ~11% chance of being defective – a high level which is attributed to the lack of cooperative NbO6 tilting in the material, which limits the lattice strain associated with each fault.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000741540300001	Publication Date	2022-01-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1477-9226	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor	4	Times cited		Open Access	OpenAccess
	Notes	Experiments at the Diamond Light Source were performed as part of the Block Allocation Group award “Oxford/Warwick Solid State Chemistry BAG to probe composition-structure-property relationships in solids” (EE18786). Experiments at the ISIS pulsed neutron facility were supported by a beam time allocation from the STFC (RB 2000148). SM thanks Somerville College for an Oxford Ryniker Lloyd scholarship. PSH and WZ thank the National Science Foundation (DMR-2002319) for support.			Approved	Most recent IF: 4
	Call Number	EMAT @ emat @c:irua:185504			Serial	6951
Permanent link to this record



	Author	Mallick, S.; Khalsa, G.; Kaaret, J.Z.; Zhang, W.; Batuk, M.; Gibbs, A.S.; Hadermann, J.; Halasyamani, P.S.; Benedek, N.A.; Hayward, M.A.
	Title	The influence of the 6s² configuration of Bi³+ on the structures of A ' BiNb₂O₇ (A ' = Rb, Na, Li) layered perovskite oxides			Type	A1 Journal article
	Year	2021	Publication	Journal of the Chemical Society : Dalton transactions	Abbreviated Journal
	Volume	50	Issue	42	Pages	15359-15369
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Solid state compounds which exhibit non-centrosymmetric crystal structures are of great interest due to the physical properties they can exhibit. The 'hybrid improper' mechanism – in which two non-polar distortion modes couple to, and stabilize, a further polar distortion mode, yielding an acentric crystal structure – offers opportunities to prepare a range of novel non-centrosymmetric solids, but examples of compounds exhibiting acentric crystal structures stabilized by this mechanism are still relatively rare. Here we describe a series of bismuth-containing layered perovskite oxide phases, RbBiNb2O7, LiBiNb2O7 and NaBiNb2O7, which have structural frameworks compatible with hybrid-improper ferroelectricity, but also contain Bi3+ cations which are often observed to stabilize acentric crystal structures due to their 6s(2) electronic configurations. Neutron powder diffraction analysis reveals that RbBiNb2O7 and LiBiNb2O7 adopt polar crystal structures (space groups I2cm and B2cm respectively), compatible with stabilization by a trilinear coupling of non-polar and polar modes. The Bi3+ cations present are observed to enhance the magnitude of the polar distortions of these phases, but are not the primary driver for the acentric structure, as evidenced by the observation that replacing the Bi3+ cations with Nd3+ cations does not change the structural symmetry of the compounds. In contrast the non-centrosymmetric, but non-polar structure of NaBiNb2O7 (space group P2(1)2(1)2(1)) differs significantly from the centrosymmetric structure of NaNdNb2O7, which is attributed to a second-order Jahn-Teller distortion associated with the presence of the Bi3+ cations.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000706651100001	Publication Date	2021-10-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1477-9234	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access	OpenAccess
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:182584			Serial	6893
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	Author	Tarakanova, E.N.; Tarakanov, P.A.; Simakov, A.O.; Furuyama, T.; Kobayashi, N.; Konev, D.V.; Goncharova, O.A.; Trashin, S.A.; De Wael, K.; Sulimenkov, I.V.; Filatov, V.V.; Kozlovskiy, V.I.; Tomilova, L.G.; Stuzhin, P.A.; Pushkarev, V.E.
	Title	Synthesis and characterization of heteroleptic rare earth double-decker complexes involving tetradiazepinoporphyrazine and phthalocyanine macrocycles			Type	A1 Journal article
	Year	2021	Publication	Dalton Transactions	Abbreviated Journal	Dalton T
	Volume	50	Issue	18	Pages	6245-6255
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Reaction of (2,3,9,10,16,17,23,24-octabutylphthalocyaninato)lanthanide(iii) acetylacetonates ((Bu)PcLn(acac), 1a-c, Ln = Lu (a), Eu (b), La (c)) with a tetrakis(5,7-bis(4-tert-butylphenyl)-6H-1,4-diazepino)[2,3-b,g,l,q]porphyrazine ligand ((tBuPh)DzPzH(2), 2) produced sandwich compounds ((tBuPh)DzPz)Ln(Pc-Bu) (3a-c), which represent the first heteroleptic double-deckers incorporating both Pc and DzPz decks. A combination of high-resolution mass spectrometry, UV-Vis/NIR, MCD, and H-1 NMR spectroscopy, and square-wave voltammetry provided unambiguous characterization of target complexes 3 indicating that their spectral and electrochemical properties are generally intermediate with respect to their homoleptic relatives. Based on the data of solution-state H-1-H-1 NMR (COSY, NOESY) correlation spectroscopy supported by DFT calculations, a dimerization tendency of compounds 3 proportional to the Ln(iii) ion size was found. The spectroelectrochemical study of 3 and the corresponding homoleptic double-deckers revealed a pronounced tendency to aggregation of the one-electron oxidized forms of DzPz-containing double-decker complexes compared to homoleptic Pc(2)Ln compounds.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000641283000001	Publication Date	2021-04-01
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1477-9226; 1477-9234	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.029	Times cited		Open Access	Not_Open_Access
	Notes				Approved	Most recent IF: 4.029
	Call Number	UA @ admin @ c:irua:178289			Serial	8636
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	Author	Paulus, A.; Hendrickx, M.; Bercx, M.; Karakulina, O.M.; Kirsanova, M.A.; Lamoen, D.; Hadermann, J.; Abakumov, A.M.; Van Bael, M.K.; Hardy, A.
	Title	An in-depth study of Sn substitution in Li-rich/Mn-rich NMC as a cathode material for Li-ion batteries			Type	A1 Journal article
	Year	2020	Publication	Journal of the Chemical Society : Dalton transactions	Abbreviated Journal
	Volume	49	Issue	30	Pages	10486-10497
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Layered Li-rich/Mn-rich NMC (LMR-NMC) is characterized by high initial specific capacities of more than 250 mA h g(-1), lower cost due to a lower Co content and higher thermal stability than LiCoO2. However, its commercialisation is currently still hampered by significant voltage fade, which is caused by irreversible transition metal ion migration to emptied Li positionsviatetrahedral interstices upon electrochemical cycling. This structural change is strongly correlated with anionic redox chemistry of the oxygen sublattice and has a detrimental effect on electrochemical performance. In a fully charged state, up to 4.8 Vvs.Li/Li+, Mn4+ is prone to migrate to the Li layer. The replacement of Mn4+ for an isovalent cation such as Sn4+ which does not tend to adopt tetrahedral coordination and shows a higher metal-oxygen bond strength is considered to be a viable strategy to stabilize the layered structure upon extended electrochemical cycling, hereby decreasing voltage fade. The influence of Sn4+ on the voltage fade in partially charged LMR-NMC is not yet reported in the literature, and therefore, we have investigated the structure and the corresponding electrochemical properties of LMR-NMC with different Sn concentrations. We determined the substitution limit of Sn4+ in Li1.2Ni0.13Co0.13Mn0.54-xSnxO2 by powder X-ray diffraction and transmission electron microscopy to be x approximate to 0.045. The limited solubility of Sn is subsequently confirmed by density functional theory calculations. Voltage fade for x= 0 andx= 0.027 has been comparatively assessed within the 3.00 V-4.55 V (vs.Li/Li+) potential window, from which it is concluded that replacing Mn4+ by Sn4+ cannot be considered as a viable strategy to inhibit voltage fade within this window, at least with the given restricted doping level.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000555330900018	Publication Date	2020-07-09
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0300-9246; 1477-9226; 1472-7773	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4	Times cited		Open Access	OpenAccess
	Notes	; The authors acknowledge Research Foundation Flanders (FWO) project number G040116N for funding. The authors are grateful to Dr Ken Elen and Greet Cuyvers (imo-imomec, UHasselt and imec) for respectively preliminary PXRD measurements and performing ICP-AES on the monometal precursors. Dr Dmitry Rupasov (Skolkovo Institute of Science and Technology) is acknowledged for performing TGA measurements on the metal sulfate precursors. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government-department EWI. ;			Approved	Most recent IF: 4; 2020 IF: 4.029
	Call Number	UA @ admin @ c:irua:171149			Serial	6450
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	Author	Mourdikoudis, S.; Montes-Garcia, V.; Rodal-Cedeira, S.; Winckelmans, N.; Perez-Juste, I.; Wu, H.; Bals, S.; Perez-Juste, J.; Pastoriza-Santos, I.
	Title	Highly porous palladium nanodendrites : wet-chemical synthesis, electron tomography and catalytic activity			Type	A1 Journal article
	Year	2019	Publication	Journal of the Chemical Society : Dalton transactions	Abbreviated Journal
	Volume	48	Issue	48	Pages	3758-3767
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	A simple procedure to obtain highly porous hydrophilic palladium nanodendrites in one-step is described. The synthetic strategy is based on the thermal reduction of a Pd precursor in the presence of a positively charged polyelectrolyte such as polyethylenimine (PEI). Advanced electron microscopy techniques combined with X-ray diffraction (XRD), thermogravimetry and BET analysis demonstrate the polycrystalline nature of the nanodendrites as well as their high porosity and active surface area, facilitating a better understanding of their unique morphology. Besides, catalytic studies performed using Raman scattering and UV-Vis spectroscopies revealed that the nanodendrites exhibit a superior performance as recyclable catalysts towards hydrogenation reaction compared to other noble metal nanoparticles.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000461088700027	Publication Date	2019-02-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0300-9246; 1477-9226; 1472-7773	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	23	Open Access	OpenAccess
	Notes	; This work was supported by the Ministerio de Economia y Competitividad (MINECO, Spain) under the Grant MAT2016-77809-R, Xunta de Galicia (GRC ED431C 2016-048 and Centro Singular de Investigacion de Galicia (ED431G/02)) and Fundacion Ramon Areces (SERSforSafety). S. M. acknowledges funding from the General Secretariat for Research and Technology in Greece (Project PE4 (1546)). S. B. and N. W. acknowledge financial support by the European Research Council (ERC Starting Grant #335078-COLOURATOMS). We thank the EPSRC CNIE Research Facility (EPSRC Award, EP/K038656/1) at the University College London for the collection of the BET data. Authors thank J. Millos for the XRD measurements. ;			Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:158530			Serial	5251
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	Author	Hasanli, N.; Gauquelin, N.; Verbeeck, J.; Hadermann, J.; Hayward, M.A.
	Title	Small-moment paramagnetism and extensive twinning in the topochemically reduced phase Sr₂ReLiO_5.5			Type	A1 Journal article
	Year	2018	Publication	Journal of the Chemical Society : Dalton transactions	Abbreviated Journal	Dalton T
	Volume	47	Issue	44	Pages	15783-15790
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Reaction of the cation-ordered double perovskite Sr2ReLiO6 with dilute hydrogen at 475 degrees C leads to the topochemical deintercalation of oxide ions from the host lattice and the formation of a phase of composition Sr2ReLiO5.5, as confirmed by thermogravimetric and EELS data. A combination of neutron and electron diffraction data reveals the reduction process converts the -Sr2O2-ReLiO4-Sr2O2-ReLiO4- stacking sequence of the parent phase into a -Sr2O2-ReLiO3-Sr2O2-ReLiO4-, partially anion-vacant ordered sequence. Furthermore a combination of electron diffraction and imaging reveals Sr2ReLiO5.5 exhibits extensive twinning – a feature which can be attributed to the large, anisotropic volume expansion of the material on reduction. Magnetisation data reveal a strongly reduced moment of (eff) = 0.505(B) for the d(1) Re6+ centres in the phase, suggesting there remains a large orbital component to the magnetism of the rhenium centres, despite their location in low symmetry coordination environments.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000450208000019	Publication Date	2018-10-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1477-9226	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor	4.029	Times cited		Open Access	Not_Open_Access
	Notes	Experiments at the Diamond Light Source were performed as part of the Block Allocation Group award “Oxford Solid State Chemistry BAG to probe composition-structure-property relationships in solids” (EE13284). Experiments at the ISIS pulsed neutron facility were supported by a beam time allocation from the STFC. NH acknowledges funding from the “State Programme on Education of Azerbaijani Youth Abroad in 2007-2015” by the Ministry of Education of Azerbaijan. J. V. and N. G. acknowledge funding through the GOA project “Solarpaint” of the University of Antwerp. The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government.			Approved	Most recent IF: 4.029
	Call Number	EMAT @ emat @c:irua:155771			Serial	5137
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	Author	Tarakanov, P.A.; Tarakanova, E.N.; Dorovatovskii, P.V.; Zubavichus, Y.V.; Khrustalev, V.N.; Trashin, S.A.; De Wael, K.; Neganova, M.E.; Mischenko, D.V.; Sessler, J.L.; Stuzhin, P.A.; Pushkarev, V.E.; Tomilova, L.G.
	Title	Optical readout of controlled monomer-dimer self-assembly			Type	A1 Journal article
	Year	2018	Publication	Journal of the Chemical Society : Dalton transactions	Abbreviated Journal
	Volume	47	Issue	40	Pages	14169-14173
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	5,7-Substituted 1,4-diazepinoporphyrazine magnesium(II) complexes were synthesized via Mg(II)-alkoxide templated macrocyclization. A single crystal growth synchrotron diffraction analysis permitted what is to our knowledge the first structural characterization of a 1,4-diazepinoporphyrazine. It exists as a dimer in the solid state. In silico calculations supported by solution phase spectral studies involving a series of representative derivatives, provided insights into the factors governing dimerization of 1,4-diazepinoporphyrazines. The present 1,4-diazepinoporphyrazines serve as useful probes for understanding the determinants that guide dimermonomer equilibria and the self-assembly of phthalocyanine derivatives.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000447708900005	Publication Date	2018-04-10
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0300-9246; 1477-9226; 1472-7773	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	4	Open Access
	Notes	; We thank Dr Alexander V. Chernyak for recording the NMR spectra. Synthetic and optical spectroscopic studies in this work were supported by the RSF (Grant 17-73-10413). NMR studies were supported by the Council under the President of the Russian Federation for State Support of Young Scientists and Leading Scientific Schools (Grant MD-2991.2017.3). SR-XRD studies were supported by the RUDN University Program “5-100”. We also acknowledge support of electrochemical, in vitro and in vivo studies by the State Assignment (Theme 45.5 Creation of compounds with given physicochemical properties) and the facilities provided by the Center of Collective Use of IPAC RAS (Chernogolovka, Russia). Single-crystal X-ray measurements have been performed at the unique scientific facility Kurchatov Synchrotron Radiation Source supported by the Ministry of Education and Science of the Russian Federation (project code RFMEFI61917X0007). ;			Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:151294			Serial	5755
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	Author	Mikhailova, D.; Kuratieva, N.N.; Utsumi, Y.; Tsirlin, A.A.; Abakumov, A.M.; Schmidt, M.; Oswald, S.; Fuess, H.; Ehrenberg, H.
	Title	Composition-dependent charge transfer and phase separation in the V1-xRexO2 solid solution			Type	A1 Journal article
	Year	2017	Publication	Journal of the Chemical Society : Dalton transactions	Abbreviated Journal
	Volume	46	Issue	5	Pages	1606-1617
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The substitution of vanadium in vanadium dioxide VO2 influences the critical temperatures of structural and metal-to-insulator transitions in different ways depending on the valence of the dopant. Rhenium adopts valence states between + 4 and + 7 in an octahedral oxygen surrounding and is particularly interesting in this context. Structural investigation of V1-xRexO2 solid solutions (0.01 <= x <= 0.30) between 80 and 1200 K using synchrotron X-ray powder diffraction revealed only two polymorphs that resemble VO2: the low-temperature monoclinic MoO2-type form (space group P2(1)/c), and the tetragonal rutile-like form (space group P4(2)/mnm). However, for compositions with 0.03 < x <= 0.15 a phase separation in the solid solution was observed below 1000 K upon cooling down from 1200 K, giving rise to two isostructural phases with slightly different lattice parameters. This is reflected in the appearance of two metal-toinsulator transition temperatures detected by magnetization and specific heat measurements. Comprehensive X-ray photoelectron spectroscopy studies showed that an increased amount of Re leads to a change in the Re valence state from solely Re6+ at a low doping level (<= 3 at% Re) via mixed-valence states Re4+/Re6+ for at least 0.03 < x <= 0.10, up to nearly pure Re4+ in V0.70Re0.30O2. Thus, compositions V1-xRexO2 with only one valence state of Re in the material (Re6+ or Re4+) can be obtained as a single phase, while intermediate compositions are subjected to a phase separation, presumably due to different valence states of Re.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000395442700030	Publication Date	2016-12-24
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0300-9246; 1477-9226; 1472-7773	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.029	Times cited	1	Open Access	Not_Open_Access
	Notes	; The authors are indebted to Dr G. Auffermann (Max Planck Institute for Chemical Physics of Solids, Dresden, Germany) for performing the ICP-OES analyses. This research has received a partial funding from the BMBF, project grant number 03SF0477B (DESIREE). AT acknowledges financial support from Federal Ministry for Education and Research under Sofja Kovalevksaya Award of Alexander von Humboldt Foundation. AMA is grateful to the Russian Science Foundation (grant 14-13-00680) for financial support. ;			Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:142580			Serial	4642
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	Author	Rozova, M.G.; Grigoriev, V.V.; Bobrikov, I.A.; Filimonov, D.S.; Zakharov, K.V.; Volkova, O.S.; Vasiliev, A.N.; Antipov, E.V.; Tsirlin, A.A.; Abakumov, A.M.
	Title	Synthesis, structure and magnetic ordering of the mullite-type Bi₂Fe_4-xCr_xO₉ solid solutions with a frustrated pentagonal Cairo lattice			Type	A1 Journal article
	Year	2016	Publication	Journal of the Chemical Society : Dalton transactions	Abbreviated Journal	Dalton T
	Volume	45	Issue	45	Pages	1192-1200
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Highly homogeneous mullite-type solid solutions Bi2Fe4-xCrxO9 (x = 0.5, 1, 1.2) were synthesized using a soft chemistry technique followed by a solid-state reaction in Ar. The crystal structure of Bi2Fe3CrO9 was investigated using X-ray and neutron powder diffraction, transmission electron microscopy and Fe-57 Mossbauer spectroscopy (S.G. Pbam, a = 7.95579(9) angstrom , b = 8.39145(9) angstrom, c = 5.98242(7) angstrom, R-F(X-ray) = 0.022, R-F(neutron) = 0.057). The ab planes in the structure are tessellated with distorted pentagonal loops built up by three tetrahedrally coordinated Fe sites and two octahedrally coordinated Fe/Cr sites, linked together in the ab plane by corner-sharing forming a pentagonal Cairo lattice. Magnetic susceptibility measurements and powder neutron diffraction show that the compounds order antiferromagnetically (AFM) with the Neel temperatures decreasing upon increasing the Cr content from T-N similar to 250 K for x = 0 to T-N similar to 155 K for x = 1.2. The magnetic structure of Bi2Fe3CrO9 at T = 30 K is characterized by a propagation vector k = (1/2,1/2,1/2). The tetrahedrally coordinated Fe cations form singlet pairs within dimers of corner-sharing tetrahedra, but spins on the neighboring dimers are nearly orthogonal. The octahedrally coordinated (Fe, Cr) cations form antiferromagnetic up-up-down-down chains along c, while the spin arrangement in the ab plane is nearly orthogonal between nearest neighbors and collinear between second neighbors. The resulting magnetic structure is remarkably different from the one in pure Bi2Fe4O9 and features several types of spin correlations even on crystallographically equivalent exchange that may be caused by the simultaneous presence of Fe and Cr on the octahedral site.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000367614700041	Publication Date	2015-11-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0300-9246; 1477-9226; 1472-7773	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.029	Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:131095			Serial	4257
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	Author	Paria Sena, R.; Babaryk, A.A.; Khainakov, S.; Garcia-Granda, S.; Slobodyanik, N.S.; Van Tendeloo, G.; Abakumov, A.M.; Hadermann, J.
	Title	A pseudo-tetragonal tungsten bronze superstructure: a combined solution of the crystal structure of K6.4(Nb,Ta)36.3O94 with advanced transmission electron microscopy and neutron diffraction			Type	A1 Journal article
	Year	2016	Publication	Journal of the Chemical Society : Dalton transactions	Abbreviated Journal	Dalton T
	Volume	45	Issue	45	Pages	973-979
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The crystal structure of the K6.4Nb28.2Ta8.1O94 pseudo-tetragonal tungsten bronze-type oxide was determined using a combination of X-ray powder diffraction, neutron diffraction and transmission electron microscopy techniques, including electron diffraction, high angle annular dark field scanning transmission electron microscopy (HAADF-STEM), annular bright field STEM (ABF-STEM) and energy-dispersive X-ray compositional mapping (STEM-EDX). The compound crystallizes in the space group Pbam with unit cell parameters a = 37.468(9) A, b = 12.493(3) A, c = 3.95333(15) A. The structure consists of corner sharing (Nb,Ta)O6 octahedra forming trigonal, tetragonal and pentagonal tunnels. All tetragonal tunnels are occupied by K(+) ions, while 1/3 of the pentagonal tunnels are preferentially occupied by Nb(5+)/Ta(5+) and 2/3 are occupied by K(+) in a regular pattern. A fractional substitution of K(+) in the pentagonal tunnels by Nb(5+)/Ta(5+) is suggested by the analysis of the HAADF-STEM images. In contrast to similar structures, such as K2Nb8O21, also parts of the trigonal tunnels are fractionally occupied by K(+) cations.
	Address	Electron Microscopy for Materials Research (EMAT), University of Antwerp, Groenenborgerlaan 171, B-2020, Antwerp, Belgium. joke.hadermann@uantwerpen.be babaryk@univ.kiev.ua
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Wos	000367614700018	Publication Date	2015-11-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1477-9226	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.029	Times cited	6	Open Access
	Notes	We thank Dr E. Suard and Dr O. Fabello for assistance in collecting the neutron diffraction data. R.P.S. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Grant No. 246791-COUNTATOMS. The titan microscope was partly funded by the Hercules fund from the Flemish Government. The authors acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative. Reference No. 312483-ESTEEM2. AAB acknowledges the JSPDS ICDD Grant-in-Aid program (12-02).; esteem2jra1; esteem2jra2			Approved	Most recent IF: 4.029
	Call Number	c:irua:130408 c:irua:130408			Serial	3998
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	Author	Charkin, D.O.; Akinfiev, V.S.; Alekseeva, A.M.; Batuk, M.; Abakumov, A.M.; Kazakov, S.M.
	Title	Synthesis and cation distribution in the new bismuth oxyhalides with the Sillen-Aurivillius intergrowth structures			Type	A1 Journal article
	Year	2015	Publication	Journal of the Chemical Society : Dalton transactions	Abbreviated Journal	Dalton T
	Volume	44	Issue	44	Pages	20568-20576
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	About 20 new compounds with the Sillen-Aurivillius intergrowth structure, (MeMeBi3Nb2O11X)-Me-1-Bi-2 (Me-1 = Pb, Sr, Ba; Me-2 = Ca, Sr, Ba; X = Cl, Br, I), have been prepared. They are composed of stacking of [ANb(2)O(7)] perovskite blocks, fluorite-type [M2O2] blocks and halogen sheets. The cation distribution between the fluorite and perovskite layers has been studied for Ba2Bi3Nb2O11I, Ca1.25Sr0.75Bi3Nb2O11Cl, BaCaBi3Nb2O11Br and Sr2Bi3Nb2O11Cl. The smaller Me cations tend to reside in the perovskite block while the larger ones are situated in the fluorite-type block. The distribution of the elements was confirmed for BaCaBi3Nb2O11Br using energy dispersive X-ray analysis combined with scanning transmission electron microscopy (STEM-EDX). An electron diffraction study of this compound reveals a local symmetry lowering caused by weakly correlated rotation of NbO6 octahedra. Based on our findings, we suggest a new stability criterion for mixed-layer structures, which is that net charges of any two consecutive layers do not compensate for each other and only the whole layer sequence is electroneutral.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000365411500036	Publication Date	2015-10-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0300-9246; 1477-9226; 1472-7773	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.029	Times cited	5	Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:130330			Serial	4256
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	Author	Lin, F.; Meng; Kukueva, E.; Altantzis, T.; Mertens, M.; Bals, S.; Cool, P.; Van Doorslaer, S.
	Title	Direct-synthesis method towards copper-containing periodic mesoporous organosilicas : detailed investigation of the copper distribution in the material			Type	A1 Journal article
	Year	2015	Publication	Journal of the Chemical Society : Dalton transactions	Abbreviated Journal	Dalton T
	Volume	44	Issue	44	Pages	9970-9979
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
	Abstract	Three-dimensional cubic Fm (3) over barm mesoporous copper-containing ethane-bridged PMO materials have been prepared through a direct-synthesis method at room temperature in the presence of cetyltrimethylammonium bromide as surfactant. The obtained materials have been unambiguously characterized in detail by several sophisticated techniques, including XRD, UV-Vis-Dr, TEM, elemental mapping, continuous- wave and pulsed EPR spectroscopy. The results show that at lower copper loading, the Cu2+ species are well dispersed in the Cu-PMO materials, and mainly exist as mononuclear Cu2+ species. At higher copper loading amount, Cu2+ clusters are observed in the materials, but the distribution of the Cu2+ species is still much better in the Cu-PMO materials prepared through the direct-synthesis method than in a Cu-containing PMO material prepared through an impregnation method. Moreover, the evolution of the copper incorporation during the PMO synthesis has been followed by EPR. The results show that the immobilization of the Cu2+ ion/complex and the formation of the PMO materials are taking place simultaneously. The copper ions are found to be situated on the inner surface of the mesopores of the materials and are accessible, which will be beneficial for the catalytic applications.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000355000700028	Publication Date	2015-04-28
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1477-9226;1477-9234;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.029	Times cited	11	Open Access	OpenAccess
	Notes	Goa-Bof; 335078 Colouratom; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot);			Approved	Most recent IF: 4.029; 2015 IF: 4.197
	Call Number	c:irua:126422			Serial	725
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	Author	Tyablikov, O.A.; Batuk, D.; Tsirlin, A.A.; Batuk, M.; Verchenko, V.Y.; Filimonov, D.S.; Pokholok, K.V.; Sheptyakov, D.V.; Rozova, M.G.; Hadermann, J.; Antipov, E.V.; Abakumov, A.M.;
	Title	{110}-Layered B-cation ordering in the anion-deficient perovskite Pb_2.4Ba_2.6Fe₂Sc₂TiO₁₃ with the crystallographic shear structure			Type	A1 Journal article
	Year	2015	Publication	Journal of the Chemical Society : Dalton transactions	Abbreviated Journal	Dalton T
	Volume	44	Issue	44	Pages	10753-10762
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	A novel anion-deficient perovskite-based compound, Pb2.4Ba2.6Fe2Sc2TiO13, was synthesized via the citrate-based route. This compound is an n = 5 member of the A(n)B(n)O(3n-2) homologous series with unit-cell parameters related to the perovskite subcell a(p) approximate to 4.0 angstrom as a(p)root 2 x a(p) x 5a(p)root 2. The crystal structure of Pb2.4Ba2.6Fe2Sc2TiO13 consists of quasi-2D perovskite blocks with a thickness of three octahedral layers separated by the 1/2[110]((1) over bar 01)(p) crystallographic shear (CS) planes, which are parallel to the {110} plane of the perovskite subcell. The CS planes transform the corner-sharing octahedra into chains of edge-sharing distorted tetragonal pyramids. Using a combination of neutron powder diffraction, Fe-57 Mossbauer spectroscopy and atomic resolution electron energy-loss spectroscopy we demonstrate that the B-cations in Pb2.4Ba2.6Fe2Sc2TiO13 are ordered along the {110} perovskite layers with Fe3+ in distorted tetragonal pyramids along the CS planes, Ti4+ preferentially in the central octahedra of the perovskite blocks and Sc3+ in the outer octahedra of the perovskite blocks. Magnetic susceptibility and Mossbauer spectroscopy indicate a broadened magnetic transition around T-N similar to 45 K and the onset of local magnetic fields at low temperatures. The magnetic order is probably reminiscent of that in other A(n)B(n)O(3n-2) homologues, where G-type AFM order within the perovskite blocks has been observed.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000355701000026	Publication Date	2015-01-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1477-9226;1477-9234;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.029	Times cited	1	Open Access
	Notes				Approved	Most recent IF: 4.029; 2015 IF: 4.197
	Call Number	c:irua:127001			Serial	22
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	Author	Mikhailova, D.; Reichel, P.; Tsirlin, A.A.; Abakumov, A.M.; Senyshyn, A.; Mogare, K.M.; Schmidt, M.; Kuo, C.Y.; Pao, C.W.; Pi, T.W.; Lee, J.F.; Hu, Z.; Tjeng, L.H.;
	Title	Oxygen-driven competition between low-dimensional structures of Sr₃CoMO₆ and Sr₃CoMO_7-\delta with M = Ru,Ir			Type	A1 Journal article
	Year	2014	Publication	Journal of the Chemical Society : Dalton transactions	Abbreviated Journal	Dalton T
	Volume	43	Issue	37	Pages	13883-13891
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	We have realized a reversible structure transformation of one-dimensional 1D K4CdCl6-type Sr3CoMO6 with the Co2+/M4+ cation ordering into the two-dimensional 2D double layered Ruddlesden-Popper structure Sr3CoMO7-delta with a random distribution of Co and M (with M = Ru, Ir) upon increasing the partial oxygen pressure. The combined soft and hard X-ray absorption spectroscopy studies show that under transformation, Co and M cations were oxidized to Co3+ and M5+. During oxidation, high-spin Co2+ in Sr3CoMO6 first transforms into high-spin Co3+ in oxygen-deficient Sr3CoMO7-delta, and then further transforms into low-spin Co3+ in fully oxidized Sr3CoMO7 upon further increasing the partial pressure of oxygen. The 1D Sr3CoMO6 compound is magnetically ordered at low temperatures with the magnetic moments lying along the c-axis. Their alignment is parallel for Sr3CoRuO6 and antiparallel for Sr3CoIrO6. The 2D compounds reveal a spin-glass-like behavior related to the random distribution of magnetic cations in the structure.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000342074100009	Publication Date	2014-07-28
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1477-9226;1477-9234;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.029	Times cited	7	Open Access
	Notes				Approved	Most recent IF: 4.029; 2014 IF: 4.197
	Call Number	UA @ lucian @ c:irua:119960			Serial	2545
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	Author	Tyutyunnik, A.P.; Slobodin, B.V.; Samigullina, R.F.; Verberck, B.; Tarakina, N.V.
	Title	K₂CaV₂O₇ : a pyrovanadate with a new layered type of structure in the A₂BV₂O₇ family			Type	A1 Journal article
	Year	2013	Publication	Journal of the Chemical Society : Dalton transactions	Abbreviated Journal	Dalton T
	Volume	42	Issue	4	Pages	1057-1064
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The crystal structure of K2CaV2O7 prepared by a conventional solid-state reaction has been solved by a direct method and refined using Rietveld full profile fitting based on X-ray powder diffraction data. This compound crystallises in the triclinic space group (P (1) over bar, Z = 2) with unit cell constants a = 7.1577(1) angstrom, b = 10.5104(2) angstrom, c = 5.8187(1) angstrom, alpha = 106.3368(9)degrees, beta = 106.235(1)degrees, gamma = 71.1375(9)degrees. The structure can be described as infinite undulating CaV2O72- layers parallel to the ac plane, which consist of pairs of edge-sharing CaO6 octahedra connected to each other through V2O7 pyrogroups. The potassium atoms are positioned in two sites between the layers, with a distorted IX-fold coordination of oxygen atoms. The chemical composition obtained from the structural solution was confirmed by energy-dispersive X-ray analysis. The stability of compounds in the family of alkali metal calcium pyrovanadates is discussed based on an analysis of the correlation between anion and cation sizes and theoretical first-principles calculations.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000312659200030	Publication Date	2012-10-04
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1477-9226;1477-9234;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.029	Times cited	3	Open Access
	Notes	; N.V.T. acknowledges funding by the Bavarian Ministry of Sciences, Research and the Arts. B. V. was financially supported by the Flemish Science Foundation (FWO-Vlaanderen). ;			Approved	Most recent IF: 4.029; 2013 IF: 4.097
	Call Number	UA @ lucian @ c:irua:105945			Serial	3536
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