|   | 
Details
   web
Records
Author Teodorescu, V.S.; Mihailescu, I.N.; Gyorgy, E.; Luches, A.; Martino, M.; Nistor, L.C.; van Landuyt, J.; Hermann, J.
Title The study of a crater forming on the surface of a Ti target submitted to multipulse excimer laser irradiation under low pressure N2 Type A1 Journal article
Year 1996 Publication Journal of modern optics Abbreviated Journal J Mod Optic
Volume 43 Issue 9 Pages 1773-1784
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A Ti target was submitted to laser ablation in low ambient pressure N-2. Electron microscopy examination of the cross-section of the crater zone forming on the Ti target, and XPS analyses, indicate that there is a small effect on the nitridation processes taking place on and in the vicinity of the target. The studies show a zone influenced by the multipulse laser treatment extending beneath the crater down to a depth of the same order of magnitude as the crater depth (i.e. similar to 10 mu m). In this zone, TiN could be identified as being present only in traces, while the whole zone exhibited a layer structure with differences in morphology and mechanical wear.
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos A1996VF31900002 Publication Date 2007-07-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0950-0340;1362-3044; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.008 Times cited 11 Open Access
Notes Approved PHYSICS, APPLIED 47/145 Q2 #
Call Number UA @ lucian @ c:irua:95238 Serial 3594
Permanent link to this record
 

 
Author Dixon, E.; Hadermann, J.; Hayward, M.A.
Title The synthesis and complex anion-vacancy ordered structure of La0.33Sr0.67MnO2.42 Type A1 Journal article
Year 2011 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 184 Issue 7 Pages 1791-1799
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The low-temperature topotactic reduction of La0.33Sr0.67MnO3 with NaH results in the formation of La0.33Sr0.67MnO2.42. A combination of neutron powder and electron diffraction data show that La0.33Sr0.67MnO2.42 adopts a novel anion-vacancy ordered structure with a 6-layer OOTOOT' stacking sequence of the octahedral and tetrahedral layers (Pcmb, a=5.5804(1) Å, b=23.4104(7) Å, c=11.2441(3) Å). A significant concentration of anion vacancies at the anion site, which links neighbouring octahedral layers means that only 25% of the octahedral manganese coordination sites actually have 6-fold MnO6 coordination, the remainder being MnO5 square-based pyramidal sites. The chains of cooperatively twisted apex-linked MnO4 tetrahedra adopt an ordered -LRLR- arrangement within each tetrahedral layer. This is the first published example of a fully refined structure of this type which exhibits such intralayer ordering of the twisted tetrahedral chains. The rationale behind the contrasting structures of La0.33Sr0.67MnO2.42 and other previously reported reduced La1−xSrxMnO3−y phases is discussed.
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000292718500032 Publication Date 2011-05-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited 8 Open Access
Notes Approved Most recent IF: 2.299; 2011 IF: 2.159
Call Number UA @ lucian @ c:irua:90885 Serial 3600
Permanent link to this record
 

 
Author Kovba, M.L.; Skolis, Y.Y.; Abakumov, A.M.; Hadermann, J.; Sukhushina, I.S.
Title The synthesis and thermodynamic properties of strontium fluoromanganite Sr2.5Mn6O12.5-\deltaF2 Type A1 Journal article
Year 2010 Publication Russian journal of physical chemistry A Abbreviated Journal Russ J Phys Chem A+
Volume 84 Issue 12 Pages 2033-2038
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The existence of the [SrF(0.8)O(0.1)](2.5)[Mn(6)O(12)] = Sr(2.5)Mn(6)O(12.5 – delta)F(2) compound was established in the SrO-Mn(2)O(3)-SrF(2) system at 900A degrees C and p(O(2)) = 1 atm. The crystal structure of strontium fluoromanganite was determined from the X-ray powder diffraction data, electron diffraction, and high-resolution electron microscopy. It can be described in the monoclynic system with four Miller hklm indices: hklm: H = h a* + k b* + l c (1) (*) + m q (1), q (1), q (1) = c (2) (*) = gamma c (1) (*) , gamma a parts per thousand 0.632, a a parts per thousand a a parts per thousand 9.72 , b a parts per thousand 9.55 , c (1) a parts per thousand 2.84 , c (2) a parts per thousand 4.49 , monoclinic angle gamma a parts per thousand 95.6A degrees. The electromotive force method with a solid fluorine ion electrolyte was used to refine the composition of fluoromanganite and determine the thermodynamic functions of its formation from phases neighboring in the phase diagram (SrMn(3)O(6), Mn(2)O(3), SrF(2), and oxygen), Delta GA degrees, kJ/mol = -(111.7 +/- 1.9) + (89.5 +/- 1.5) x 10(-3) T.
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000284775000004 Publication Date 2011-02-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0036-0244;1531-863X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 0.581 Times cited 1 Open Access
Notes Approved Most recent IF: 0.581; 2010 IF: 0.503
Call Number UA @ lucian @ c:irua:99190 Serial 3601
Permanent link to this record
 

 
Author Lajevardipour, A.; Neek-Amal, M.; Peeters, F.M.
Title Thermomechanical properties of graphene : valence force field model approach Type A1 Journal article
Year 2012 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 24 Issue 17 Pages 175303-175303,8
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using the valence force field model of Perebeinos and Tersoff (2009 Phys. Rev. B 79 241409(R)), different energy modes of suspended graphene subjected to tensile or compressive strain are studied. By carrying out Monte Carlo simulations it is found that: (i) only for small strains (vertical bar epsilon vertical bar (sic) 0.02) is the total energy symmetrical in the strain, while it behaves completely differently beyond this threshold; (ii) the important energy contributions in stretching experiments are stretching, angle bending, an out-of-plane term, and a term that provides repulsion against pi-pi misalignment; (iii) in compressing experiments the two latter terms increase rapidly, and beyond the buckling transition stretching and bending energies are found to be constant; (iv) from stretching-compressing simulations we calculated the Young's modulus at room temperature 350 +/- 3.15 N m(-1), which is in good agreement with experimental results (340 +/- 50 N m(-1)) and with ab initio results (322-353) N m(-1); (v) molar heat capacity is estimated to be 24.64 J mol(-1) K-1 which is comparable with the Dulong-Petit value, i. e. 24.94 J mol(-1) K-1, and is almost independent of the strain; (vi) nonlinear scaling properties are obtained from height-height correlations at finite temperature; (vii) the used valence force field model results in a temperature independent bending modulus for graphene, and (viii) the Gruneisen parameter is estimated to be 0.64.
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000303499700012 Publication Date 2012-04-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 29 Open Access
Notes ; We acknowledge helpful comments by V Perebeinos, S Costamagna, A Fasolino and J H Los. This work was supported by the Flemish science foundation (FWO-Vl) and the Belgium Science Policy (IAP). ; Approved Most recent IF: 2.649; 2012 IF: 2.355
Call Number UA @ lucian @ c:irua:99123 Serial 3639
Permanent link to this record
 

 
Author Dubourdieu, C.; Huot, G.; Gelard, I.; Roussel, H.; Lebedev, O.I.; Van Tendeloo, G.
Title Thin films and superlattices of multiferroic hexagonal rare earth manganites Type A1 Journal article
Year 2007 Publication Philosophical magazine letters Abbreviated Journal Phil Mag Lett
Volume 87 Issue 3/4 Pages 203-210
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000246263700008 Publication Date 2007-03-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0950-0839;1362-3036; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 0.941 Times cited 17 Open Access
Notes Approved Most recent IF: 0.941; 2007 IF: 1.878
Call Number UA @ lucian @ c:irua:64721 Serial 3640
Permanent link to this record
 

 
Author Van Aert, S.; Batenburg, K.J.; Rossell, M.D.; Erni, R.; Van Tendeloo, G.
Title Three-dimensional atomic imaging of crystalline nanoparticles Type A1 Journal article
Year 2011 Publication Nature Abbreviated Journal Nature
Volume 470 Issue 7334 Pages 374-377
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract Determining the three-dimensional (3D) arrangement of atoms in crystalline nanoparticles is important for nanometre-scale device engineering and also for applications involving nanoparticles, such as optoelectronics or catalysis. A nanoparticles physical and chemical properties are controlled by its exact 3D morphology, structure and composition1. Electron tomography enables the recovery of the shape of a nanoparticle from a series of projection images2, 3, 4. Although atomic-resolution electron microscopy has been feasible for nearly four decades, neither electron tomography nor any other experimental technique has yet demonstrated atomic resolution in three dimensions. Here we report the 3D reconstruction of a complex crystalline nanoparticle at atomic resolution. To achieve this, we combined aberration-corrected scanning transmission electron microscopy5, 6, 7, statistical parameter estimation theory8, 9 and discrete tomography10, 11. Unlike conventional electron tomography, only two images of the targeta silver nanoparticle embedded in an aluminium matrixare sufficient for the reconstruction when combined with available knowledge about the particles crystallographic structure. Additional projections confirm the reliability of the result. The results we present help close the gap between the atomic resolution achievable in two-dimensional electron micrographs and the coarser resolution that has hitherto been obtained by conventional electron tomography.
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000287409100037 Publication Date 2011-02-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0028-0836;1476-4687; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 40.137 Times cited 341 Open Access
Notes Esteem 026019 Approved Most recent IF: 40.137; 2011 IF: 36.280
Call Number UA @ lucian @ c:irua:86745 Serial 3644
Permanent link to this record
 

 
Author Schweigert, V.A.; Peeters, F.M.
Title Time dependent properties of classical artificial atoms Type A1 Journal article
Year 1998 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 10 Issue Pages 2417-2435
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000072951000006 Publication Date 2002-08-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 18 Open Access
Notes Approved Most recent IF: 2.649; 1998 IF: 1.645
Call Number UA @ lucian @ c:irua:24175 Serial 3665
Permanent link to this record
 

 
Author Van Tendeloo, G.; op de Beeck, M.; De Meulenaere, P.; van Dyck, D.
Title Towards quantitative high resolution electron microscopy? Type A1 Journal article
Year 1995 Publication Institute of physics conference series Abbreviated Journal
Volume 147 Issue Pages 67-72
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract The basics of the interpretation of high resolution images showing detail of the order of 0.1 nm are shortly explained here. The use of a field emission source, a CCD camera and an adapted reconstruction method for restoring the projected crystal potential (focus variation method) allows a quantitative interpretation of HREM images. Examples of partially disordered alloys and carbonate ordering in high Tc superconductors are presented.
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos A1995BE67F00014 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0-7503-0357-3; 0951-3248; 0305-2346 ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:13015 Serial 3688
Permanent link to this record
 

 
Author Zhang, Z.; Ma, L.N.; Liao, X.Z.; van Landuyt, J.
Title A transmission electron-microscopy study of crystalline surface domains on al-co decagonal quasi-crystals and the \tau2-Al13CO4 approximant Type A1 Journal article
Year 1994 Publication Philosophical magazine letters Abbreviated Journal Phil Mag Lett
Volume 70 Issue 5 Pages 303-310
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Twin-domains of a b.c.c. crystalline phase with a = 0.29 nm have been found in a surface layer on surfaces of Al-Co decagonal quasicrystals and the coexisting tau(2)-Al13Co4 crystalline approximant. These surface layer domains are introduced during the preparation of electron microscopy thin films by ion milling.
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos A1994PQ20900008 Publication Date 2007-07-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0950-0839;1362-3036; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.087 Times cited 4 Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:99816 Serial 3715
Permanent link to this record
 

 
Author Zhang, Z.; Geng, W.; van Landuyt, J.; Van Tendeloo, G.
Title A transmission electron microscopy study of tweed-like structures in Al62Cu17.5CO17.5Si3 decagonal quasicrystals Type A1 Journal article
Year 1995 Publication Philosophical magazine: A: physics of condensed matter: defects and mechanical properties Abbreviated Journal
Volume 71 Issue 5 Pages 1177-1189
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos A1995QW79500016 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0141-8610; 1364-2804 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 7 Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:13296 Serial 3721
Permanent link to this record
 

 
Author Wang, H.; Cuppens, J.; Biermans, E.; Bals, S.; Fernandez-Ballester, L.; Kvashnina, K.O.; Bras, W.; van Bael, M.J.; Temst, K.; Vantomme, A.
Title Tuning of the size and the lattice parameter of ion-beam synthesized Pb nanoparticles embedded in Si Type A1 Journal article
Year 2012 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 45 Issue 3 Pages 035301-035301,7
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The size and lattice constant evolution of Pb nanoparticles (NPs) synthesized by high fluence implantation in crystalline Si have been studied with a variety of experimental techniques. Results obtained from small-angle x-ray scattering showed that the Pb NPs grow with increasing implantation fluence and annealing duration. The theory of NP growth kinetics can be applied to qualitatively explain the size evolution of the Pb NPs during the implantation and annealing processes. Moreover, the lattice constant of the Pb NPs was evaluated by conventional x-ray diffraction. The lattice dilatation was observed to decrease with increasing size of the Pb NPs. Such lattice constant tuning can be attributed to the pseudomorphism caused by the lattice mismatch between the Pb NPs and the Si matrix.
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000299308400008 Publication Date 2011-12-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727;1361-6463; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited 5 Open Access
Notes Fwo; Iap Approved Most recent IF: 2.588; 2012 IF: 2.528
Call Number UA @ lucian @ c:irua:94208 Serial 3754
Permanent link to this record
 

 
Author Rosova, A.; Krekels, T.; Van Tendeloo, G.; Darriet, B.; Chambon, M.
Title Twin boundary structure of Au-doped YBa2Cu3O7-x single crystals Type A1 Journal article
Year 1993 Publication Ferroelectrics Abbreviated Journal Ferroelectrics
Volume 141 Issue Pages 87-94
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0015-0193 ISBN Additional Links UA library record
Impact Factor 0.469 Times cited Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:7502 Serial 3766
Permanent link to this record
 

 
Author Ferreira, W.P.; Farias, G.A.; Peeters, F.M.
Title A two-component mixture of charged particles confined in a channel: melting Type A1 Journal article
Year 2010 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 22 Issue 28 Pages 11
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The melting of a binary system of charged particles confined in a quasi-one-dimensional parabolic channel is studied through Monte Carlo simulations. At zero temperature the particles are ordered in parallel chains. The melting is anisotropic and different melting temperatures are obtained according to the spatial direction, and the different kinds of particles present in the system. Melting is very different for the single-, two- and four-chain configurations. A temperature induced structural phase transition is found between two different four-chain ordered states which is absent in the mono-disperse system. In the mixed regime, where the two kinds of particles are only slightly different, melting is almost isotropic and a thermally induced homogeneous distribution of the distinct kinds of charges is observed.
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000279257300023 Publication Date 2010-06-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 10 Open Access
Notes ; This work was supported by CNPq, the Flemish Science Foundation (FWO-V1) and the bilateral program between Flanders and Brazil. ; Approved Most recent IF: 2.649; 2010 IF: 2.332
Call Number UA @ lucian @ c:irua:83862 Serial 3771
Permanent link to this record
 

 
Author Croitoru, M.D.; Shanenko, A.A.; Kaun, C.C.; Peeters, F.M.
Title Ultra-small metallic grains : effect of statistical fluctuations of the chemical potential on superconducting correlations and vice versa Type A1 Journal article
Year 2012 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 24 Issue 27 Pages 275701
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Superconducting correlations in an isolated metallic grain are governed by the interplay between two energy scales: the mean level spacing delta and the bulk pairing gap Delta(0), which are strongly influenced by the position of the chemical potential with respect to the closest single-electron level. In turn superconducting correlations affect the position of the chemical potential. Within the parity projected BCS model we investigate the probability distribution of the chemical potential in a superconducting grain with randomly distributed single-electron levels. Taking into account statistical fluctuations of the chemical potential due to the pairing interaction, we find that such fluctuations have a significant impact on the critical level spacing delta(c) at which the superconducting correlations cease: the critical ratio delta(c)/Delta(0) at which superconductivity disappears is found to be increased.
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000305653100012 Publication Date 2012-06-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 9 Open Access
Notes ; This work was supported by the European Community under the Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR), the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF network INSTANS. MDC and AAS are grateful to A Vagov for stimulating discussions. ; Approved Most recent IF: 2.649; 2012 IF: 2.355
Call Number UA @ lucian @ c:irua:100280 Serial 3793
Permanent link to this record
 

 
Author Dufour, T.; Minnebo, J.; Abou Rich, S.; Neyts, E.C.; Bogaerts, A.; Reniers, F.
Title Understanding polyethylene surface functionalization by an atmospheric He/O2 plasma through combined experiments and simulations Type A1 Journal article
Year 2014 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 47 Issue 22 Pages 224007
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract High density polyethylene surfaces were exposed to the atmospheric post-discharge of a radiofrequency plasma torch supplied in helium and oxygen. Dynamic water contact angle measurements were performed to evaluate changes in surface hydrophilicity and angle resolved x-ray photoelectron spectroscopy was carried out to identify the functional groups responsible for wettability changes and to study their subsurface depth profiles, up to 9 nm in depth. The reactions leading to the formation of CO, C = O and OC = O groups were simulated by molecular dynamics. These simulations demonstrate that impinging oxygen atoms do not react immediately upon impact but rather remain at or close to the surface before eventually reacting. The simulations also explain the release of gaseous species in the ambient environment as well as the ejection of low molecular weight oxidized materials from the surface.
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000336207900008 Publication Date 2014-05-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727;1361-6463; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited 13 Open Access
Notes Approved Most recent IF: 2.588; 2014 IF: 2.721
Call Number UA @ lucian @ c:irua:116919 Serial 3804
Permanent link to this record
 

 
Author Adam, N.; Leroux, F.; Knapen, D.; Bals, S.; Blust, R.
Title The uptake of ZnO and CuO nanoparticles in the water-flea Daphnia magna under acute exposure scenarios Type A1 Journal article
Year 2014 Publication Environmental pollution Abbreviated Journal Environ Pollut
Volume 194 Issue Pages 130-137
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Veterinary physiology and biochemistry
Abstract In this study the uptake of ZnO and CuO nanoparticles by Daphnia magna was tested. Daphnids were exposed during 48 h to acute concentrations of the nanoparticles and corresponding metal salts. The Daphnia zinc and copper concentration was measured and the nanoparticles were localized using electron microscopy. The aggregation and dissolution in the medium was characterized. A fast dissolution of ZnO in the medium was observed, while most CuO formed large aggregates and only a small fraction dissolved. The Daphnia zinc concentration was comparable for the nanoparticles and salts. Contrarily, a much higher Daphnia copper concentration was observed in the CuO exposure, compared to the copper salt. CuO nanoparticles adsorbed onto the carapace and occurred in the gut but did not internalize in the tissues. The combined dissolution and uptake results indicate that the toxicity of both nanoparticle types was caused by metal ions dissolved from the particles in the medium.
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000342530800016 Publication Date 2014-08-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0269-7491; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.099 Times cited 45 Open Access Not_Open_Access
Notes ; We would like to thank Valentine Mubiana and Steven Joosen (Sphere, UA) for performing the ICP-OES and ICP-MS measurements and Prof. Dr. Gustaaf Van Tendeloo for making the collaboration between the EMAT and Sphere group possible. Additional thanks go to the European Commission for funding this work through the project ENNSATOX (NMP4-SL-2009-229244). ; Approved Most recent IF: 5.099; 2014 IF: 4.143
Call Number UA @ lucian @ c:irua:118326 Serial 3823
Permanent link to this record
 

 
Author Pereira, J.M.; Peeters, F.M.; Costa Filho, R.N.; Farias, G.A.
Title Valley polarization due to trigonal warping on tunneling electrons in graphene Type A1 Journal article
Year 2009 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 21 Issue 4 Pages 045301,1-045301,4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The effect of trigonal warping on the transmission of electrons tunneling through potential barriers in graphene is investigated. We present calculations of the transmission coefficient for single and double barriers as a function of energy, incidence angle and barrier heights. The results show remarkable valley-dependent directional effects for barriers oriented parallel to the armchair or parallel to the zigzag direction. These results indicate that electrostatic gates can be used as valley filters in graphene-based devices.
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000262354700004 Publication Date 2008-12-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 78 Open Access
Notes Approved Most recent IF: 2.649; 2009 IF: 1.964
Call Number UA @ lucian @ c:irua:75736 Serial 3834
Permanent link to this record
 

 
Author Simon, P.; Bogaerts, A.
Title Vibrational level population of nitrogen impurities in low-pressure argon glow discharges Type A1 Journal article
Year 2011 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom
Volume 26 Issue 4 Pages 804-810
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The vibrational level populations of the electronic ground state of the nitrogen molecule have been calculated for typical glow discharge conditions in argonnitrogen mixtures with nitrogen concentrations between 0.1 and 1%. Stationary solutions of the master equations of the vibrational levels have been obtained using numerical methods. The main mechanisms responsible for the population and depopulation of the vibrational levels, and for the overall shape of the vibrational distribution function are pointed out. It has been found that vibrationvibration collisions play only a minor role and therefore the population of the vibrational levels is basically determined by the electron temperature.
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000288703300012 Publication Date 2010-12-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0267-9477;1364-5544; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.379 Times cited 6 Open Access
Notes Approved Most recent IF: 3.379; 2011 IF: 3.220
Call Number UA @ lucian @ c:irua:87530 Serial 3842
Permanent link to this record
 

 
Author Chen, J.H.; Bernaerts, D.; Seo, J.W.; Van Tendeloo, G.; Kagi, H.
Title Voidites in polycrystalline natural diamond Type A1 Journal article
Year 1998 Publication Philosophical magazine letters Abbreviated Journal Phil Mag Lett
Volume 77 Issue 3 Pages 135-140
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000072112000002 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0950-0839;1362-3036; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 0.941 Times cited 7 Open Access
Notes Approved Most recent IF: 0.941; 1998 IF: 1.152
Call Number UA @ lucian @ c:irua:25688 Serial 3849
Permanent link to this record
 

 
Author Xu, W.; Peeters, F.M.; Devreese, J.T.
Title Warm-electron transport in a two-dimensional semiconductor Type A1 Journal article
Year 1992 Publication Semiconductor science and technology Abbreviated Journal Semicond Sci Tech
Volume 7 Issue Pages 1251-1256
Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos A1992JT73000006 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0268-1242 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.19 Times cited 3 Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:2915 Serial 3903
Permanent link to this record
 

 
Author Rakhimov, K.Y.; Chaves, A.; Farias, G.A.; Peeters, F.M.
Title Wavepacket scattering of Dirac and Schrödinger particles on potential and magnetic barriers Type A1 Journal article
Year 2011 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 23 Issue 27 Pages 275801,1-275801,16
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We investigate the dynamics of a charged particle moving in a graphene layer and in a two-dimensional electron gas, where it obeys the Dirac and the Schrödinger equations, respectively. The charge carriers are described as Gaussian wavepackets. The dynamics of the wavepackets is studied numerically by solving both quantum-mechanical and relativistic equations of motion. The scattering of such wavepackets by step-like magnetic and potential barriers is analysed for different values of wavepacket energy and width. We find: (1) that the average position of the wavepacket does not coincide with the classical trajectory, and (2) that, for slanted incidence, the path of the centre of mass of the wavepacket does not have to penetrate the barrier during the scattering process. Trembling motion of the charged particle in graphene is observed in the absence of an external magnetic field and can be enhanced by a substrate-induced mass term.
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000291993600009 Publication Date 2011-06-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 32 Open Access
Notes ; Discussions with A Matulis are gratefully acknowledged. KR is beneficiary of a mobility grant from the Belgian Federal Science Policy Office, co-funded by the European Commission and was supported in part by a grant of the Third World Academy of Sciences (ref. 09-188 RG/PHYS/AS-I). In addition, this work was financially supported by CNPq, under contract NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES, the Bilateral programme between Flanders and Brazil, the joint project CNPq-FWO, the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 2.649; 2011 IF: 2.546
Call Number UA @ lucian @ c:irua:90880 Serial 3908
Permanent link to this record
 

 
Author de de Meux, A.J.; Pourtois, G.; Genoe, J.; Heremans, P.
Title Comparison of the electronic structure of amorphous versus crystalline indium gallium zinc oxide semiconductor : structure, tail states and strain effects Type A1 Journal article
Year 2015 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 48 Issue 48 Pages 435104
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We study the evolution of the structural and electronic properties of crystalline indium gallium zinc oxide (IGZO) upon amorphization by first-principles calculation. The bottom of the conduction band (BCB) is found to be constituted of a pseudo-band of molecular orbitals that resonate at the same energy on different atomic sites. They display a bonding character between the s orbitals of the metal sites and an anti-bonding character arising from the interaction between the oxygen and metal s orbitals. The energy level of the BCB shifts upon breaking of the crystal symmetry during the amorphization process, which may be attributed to the reduction of the coordination of the cationic centers. The top of the valence band (TVB) is constructed from anti-bonding oxygen p orbitals. In the amorphous state, they have random orientation, in contrast to the crystalline state. This results in the appearance of localized tail states in the forbidden gap above the TVB. Zinc is found to play a predominant role in the generation of these tail states, while gallium hinders their formation. Last, we study the dependence of the fundamental gap and effective mass of IGZO on mechanical strain. The variation of the gap under strain arises from the enhancement of the anti-bonding interaction in the BCB due to the modification of the length of the oxygen-metal bonds and/or to a variation of the cation coordination. This effect is less pronounced for the amorphous material compared to the crystalline material, making amorphous IGZO a semiconductor of choice for flexible electronics. Finally, the effective mass is found to increase upon strain, in contrast to regular materials. This counterintuitive variation is due to the reduction of the electrostatic shielding of the cationic centers by oxygen, leading to an increase of the overlaps between the metal orbitals at the origin of the delocalization of the BCB. For the range of strain typically met in flexible electronics, the induced variation in the effective mass is found to be negligible (less than 1%).
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000365876300012 Publication Date 2015-09-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited 23 Open Access
Notes Approved Most recent IF: 2.588; 2015 IF: 2.721
Call Number UA @ lucian @ c:irua:130277 Serial 4153
Permanent link to this record
 

 
Author Sivek, J.; Sahin, H.; Partoens, B.; Peeters, F.M.
Title Giant magnetic anisotropy in doped single layer molybdenum disulfide and fluorographene Type A1 Journal article
Year 2016 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 28 Issue 28 Pages 195301
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Stable monolayer materials based on existing, well known and stable two-dimensional crystal fluorographene and molybdenum disulfide are predicted to exhibit a huge magnetocrystalline anisotropy when functionalized with adsorbed transition metal atoms at vacant sides. Ab initio calculations within the density-functional theory formalism were performed to investigate the adsorption of the transitional metals in a single S (or F) vacancy of monolayer molybdenum disulfide (or fluorographene). We found strong bonding of the transitional metal atoms to the vacant sites with binding energies ranging from 2.5 to 5.2 eV. Our calculations revealed that these systems with adsorbed metal atoms exhibit a magnetic anisotropy, specifically the structures including Os and Ir show a giant magnetocrystalline anisotropy energy of 31-101 meV. Our results demonstrate the possibility of obtaining stable monolayer materials with huge magnetocrystalline anisotropy based on preexisting, well known and stable two-dimensional crystals: fluorographene and molybdenum disulfide. We believe that the results obtained here are useful not only for deeper understanding of the origin of magnetocrystalline anisotropy but also for the design of monolayer optoelectronic devices with novel functionalities.
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000374394700007 Publication Date 2016-04-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 7 Open Access
Notes Approved Most recent IF: 2.649
Call Number UA @ lucian @ c:irua:133611 Serial 4185
Permanent link to this record
 

 
Author Zarenia, M.; Perali, A.; Peeters, F.M.; Neilson, D.
Title Large gap electron-hole superfluidity and shape resonances in coupled graphene nanoribbons Type A1 Journal article
Year 2016 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 6 Issue 6 Pages 24860
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We predict enhanced electron-hole superfluidity in two coupled electron-hole armchair-edge terminated graphene nanoribbons separated by a thin insulating barrier. In contrast to graphene monolayers, the multiple subbands of the nanoribbons are parabolic at low energy with a gap between the conduction and valence bands, and with lifted valley degeneracy. These properties make screening of the electron-hole interaction much weaker than for coupled electron-hole monolayers, thus boosting the pairing strength and enhancing the superfluid properties. The pairing strength is further boosted by the quasi one-dimensional quantum confinement of the carriers, as well as by the large density of states near the bottom of each subband. The latter magnifies superfluid shape resonances caused by the quantum confinement. Several superfluid partial condensates are present for finite-width nanoribbons with multiple subbands. We find that superfluidity is predominately in the strongly-coupled BEC and BCS-BEC crossover regimes, with large superfluid gaps up to 100 meV and beyond. When the gaps exceed the subband spacing, there is significant mixing of the subbands, a rounding of the shape resonances, and a resulting reduction in the one-dimensional nature of the system.
Address
Corporate Author Thesis
Publisher Nature Publishing Group Place of Publication (up) London Editor
Language Wos 000374654500002 Publication Date 2016-04-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.259 Times cited 7 Open Access
Notes ; M.Z. acknowledges support by the Flemish Science Foundation (FWO-Vl), the University Research Fund (BOF), and the European Science Foundation (POLATOM). A.P. and D.N. acknowledge support by the University of Camerino FAR project CESEMN. The authors thank the colleagues involved in the MultiSuper International Network (http://www.multisuper.org) for exchange of ideas and suggestions for this work. ; Approved Most recent IF: 4.259
Call Number UA @ lucian @ c:irua:133619 Serial 4201
Permanent link to this record
 

 
Author Schouteden, K.; Li, Z.; Chen, T.; Song, F.; Partoens, B.; Van Haesendonck, C.; Park, K.
Title Moire superlattices at the topological insulator Bi2Te3 Type A1 Journal article
Year 2016 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 6 Issue 6 Pages 20278
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We report on the observation of complex superlattices at the surface of the topological insulator Bi2Te3. Scanning tunneling microscopy reveals the existence of two different periodic structures in addition to the Bi2Te3 atomic lattice, which is found to strongly affect the local electronic structure. These three different periodicities are interpreted to result from a single small in-plane rotation of the topmost quintuple layer only. Density functional theory calculations support the observed increase in the DOS near the Fermi level, and exclude the possibility that strain is at the origin of the observed Moire pattern. Exploration of Moire superlattices formed by the quintuple layers of topological insulators holds great potential for further tuning of the properties of topological insulators.
Address
Corporate Author Thesis
Publisher Nature Publishing Group Place of Publication (up) London Editor
Language Wos 000369543200001 Publication Date 2016-02-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.259 Times cited 14 Open Access
Notes ; The research in Leuven and Antwerp has been supported by the Research Foundation – Flanders (FWO, Belgium). The research in Leuven received additional support from the Flemish Concerted Research Action program (BOF KU Leuven, Project No. GOA/14/007). Z.L. thanks the China Scholarship Council for financial support (No. 2011624021). K.S. acknowledges support from the FWO. K.P. was supported by U.S. National Science Foundation DMR-1206354 and San Diego Supercomputer Center (SDSC) Trestles under DMR060009N. T.C. and F.S. acknowledge the financial support of the National Key Projects for Basic Research of China (Grant Nos: 2013CB922103), the National Natural Science Foundation of China (Grant Nos: 91421109, 11522432), the PAPD project, and the Natural Science Foundation of Jiangsu Province (Grant BK20130054). ; Approved Most recent IF: 4.259
Call Number UA @ lucian @ c:irua:131612 Serial 4208
Permanent link to this record
 

 
Author Croitoru, M.D.; Shanenko, A.A.; Vagov, A.; Milošević, M.V.; Axt, V.M.; Peeters, F.M.
Title Phonon limited superconducting correlations in metallic nanograins Type A1 Journal article
Year 2015 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 5 Issue 5 Pages 16515
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Conventional superconductivity is inevitably suppressed in ultra-small metallic grains for characteristic sizes smaller than the Anderson limit. Experiments have shown that above the Anderson limit the critical temperature may be either enhanced or reduced when decreasing the particle size, depending on the superconducting material. In addition, there is experimental evidence that whether an enhancement or a reduction is found depends on the strength of the electronphonon interaction in the bulk. We reveal how the strength of the e-ph interaction interplays with the quantum-size effect and theoretically obtain the critical temperature of the superconducting nanograins in excellent agreement with experimental data. We demonstrate that strong e-ph scattering smears the peak structure in the electronic density-of-states of a metallic grain and enhances the electron mass, and thereby limits the highest T-c achievable by quantum confinement.
Address
Corporate Author Thesis
Publisher Nature Publishing Group Place of Publication (up) London Editor
Language Wos 000364647700001 Publication Date 2015-11-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.259 Times cited 9 Open Access
Notes ; This work was supported by the Belgian Science Policy (BELSPO Back to Belgium Grant), the Research Foundation Flanders (FWO), the Methusalem Foundation of the Flemish Government, TOPBOF-UA, and the bilateral project CNPq-FWO. M.D.C. acknowledges fruitful discussions with V. Z. Kresin, S. N. Klimin and V. N. Gladilin. ; Approved Most recent IF: 4.259; 2015 IF: 5.578
Call Number UA @ lucian @ c:irua:129543 Serial 4224
Permanent link to this record
 

 
Author Ryabova, A.S.; Napolskiy, F.S.; Poux, T.; Istomin, S.Y.; Bonnefont, A.; Antipin, D.M.; Baranchikov, A.Y.; Levin, E.E.; Abakumov, A.M.; Kéranguéven, G.; Antipov, E.V.; Tsirlina, G.A.; Savinova, E.R.;
Title Rationalizing the influence of the Mn(IV)/Mn(III) red-Ox transition on the electrocatalytic activity of manganese oxides in the oxygen reduction reaction Type A1 Journal article
Year 2016 Publication Electrochimica acta Abbreviated Journal Electrochim Acta
Volume 187 Issue 187 Pages 161-172
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Knowledge on the mechanisms of oxygen reduction reaction (ORR) and descriptors linking the catalytic activity to the structural and electronic properties of transition metal oxides enable rational design of more efficient catalysts. In this work ORR electrocatalysis was studied on a set of single and complex Mn (III) oxides with a rotating disc electrode method and cyclic voltammetry. We discovered an exponential increase of the specific electrocatalytic activity with the potential of the surface Mn(IV)/Mn(III) red-ox couple, suggesting the latter as a new descriptor for the ORR electrocatalysis. The observed dependence is rationalized using a simple mean-field kinetic model considering availability of the Mn( III) centers and adsorbate-adsorbate interactions. We demonstrate an unprecedented activity of Mn2O3, ca. 40 times exceeding that of MnOOH and correlate the catalytic activity of Mn oxides to their crystal structure. (C) 2015 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication (up) London Editor
Language Wos 000367235600019 Publication Date 2015-11-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.798 Times cited 51 Open Access
Notes Approved Most recent IF: 4.798
Call Number UA @ lucian @ c:irua:131096 Serial 4237
Permanent link to this record
 

 
Author Curran, P.J.; Desoky, W.M.; Milošević, M.V.; Chaves, A.; Laloe, J.-B.; Moodera, J.S.; Bending, S.J.
Title Spontaneous symmetry breaking in vortex systems with two repulsive lengthscales Type A1 Journal article
Year 2015 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 5 Issue 5 Pages 15569
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Scanning Hall probe microscopy (SHPM) has been used to study vortex structures in thin epitaxial films of the superconductor MgB2. Unusual vortex patterns observed in MgB2 single crystals have previously been attributed to a competition between short-range repulsive and long-range attractive vortex-vortex interactions in this two band superconductor; the type 1.5 superconductivity scenario. Our films have much higher levels of disorder than bulk single crystals and therefore both superconducting condensates are expected to be pushed deep into the type 2 regime with purely repulsive vortex interactions. We observe broken symmetry vortex patterns at low fields in all samples after field-cooling from above T-c. These are consistent with those seen in systems with competing repulsions on disparate length scales, and remarkably similar structures are reproduced in dirty two band Ginzburg-Landau calculations, where the simulation parameters have been defined by experimental observations. This suggests that in our dirty MgB2 films, the symmetry of the vortex structures is broken by the presence of vortex repulsions with two different lengthscales, originating from the two distinct superconducting condensates. This represents an entirely new mechanism for spontaneous symmetry breaking in systems of superconducting vortices, with important implications for pinning phenomena and high current density applications.
Address
Corporate Author Thesis
Publisher Nature Publishing Group Place of Publication (up) London Editor
Language Wos 000363306000002 Publication Date 2015-10-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.259 Times cited 12 Open Access
Notes ; P.J.C. and S.J.B. acknowledge support from EPSRC in the UK under grant number EP/J010626/1 and the NanoSC COST Action MP-1201. M.V.M. thanks the Research Foundation-Flanders (FWO) and CAPES Brazil. A.C. acknowledges the financial support of CNPq, under the PRONEX/FUNCAP and PQ programs. J.-B.L. and J.S.M. acknowledge ONR Grant N00014-06-01-0235. ; Approved Most recent IF: 4.259; 2015 IF: 5.578
Call Number UA @ lucian @ c:irua:129450 Serial 4248
Permanent link to this record
 

 
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 (up) 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
Permanent link to this record
 

 
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 Bi2Fe4-xCrxO9 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 (up) 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
Permanent link to this record