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Author Retuerto, M.; Li, M.R.; Go, Y.B.; Ignatov, A.; Croft, M.; Ramanujachary, K.V.; Herber, R.H.; Nowik, I.; Hodges, J.P.; Dachraoui, W.; Hadermann, J.; Greenblatt, M.;
Title High magnetic ordering temperature in the perovskites Sr4-xLaxFe3ReO12 (x=0.0, 1.0, 2.0) Type A1 Journal article
Year 2012 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 194 Issue Pages 48-58
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A series of perovskites Sr4−xLaxFe3ReO12 (x=0.0, 1.0, 2.0) has been prepared by wet chemistry methods. The structure analyses by powder X-ray and neutron diffraction and electron microscopy show that these compounds adopt simple perovskite structures without cation ordering over the B sites: tetragonal (I4/mcm) for x=0.0 and 1.0 and orthorhombic (Pbmn) for x=2.0. The oxidation states of the cations in the compound with x=0.0 appear to be Fe3+/4+ and Re7+ and decrease for both with La substitution as evidenced by X-ray absorption spectroscopy. All the compounds are antiferromagnetically ordered above room temperature, as demonstrated by Mössbauer spectroscopy and the magnetic structures, which were determined by powder neutron diffraction. The substitution of Sr by La strongly affects the magnetic properties with an increase of TN up to ∼750 K.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000308896400009 Publication Date 2012-07-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited 9 Open Access
Notes Approved Most recent IF: 2.299; 2012 IF: 2.040
Call Number (up) UA @ lucian @ c:irua:101220 Serial 1435
Permanent link to this record
 
 
Author Somers, W.; Bogaerts, A.; van Duin, A.C.T.; Neyts, E.C.
Title Plasma species interacting with nickel surfaces : toward an atomic scale understanding of plasma-catalysis Type A1 Journal article
Year 2012 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 116 Issue 39 Pages 20958-20965
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The adsorption probability and reaction behavior of CHx plasma species on various nickel catalyst surfaces is investigated by means of reactive molecular dynamics (MD) simulations using the ReaxFF potential. Such catalysts are used in the reforming of hydrocarbons and in the growth of carbon nanotubes, and further insight in the underlying mechanisms of these processes is needed to increase their applicability. Single and consecutive impacts of CHx radicals (x={1,2,3}) were performed on four different Ni surfaces, at a temperature of 400 K. The adsorption probability is shown to be related to the number of free electrons, i.e. a higher number leads to more adsorptions, and the steric hindrance caused by the hydrogen atoms bonded to the impacting CHx species. Furthermore, some of the CH bonds break after adsorption, which generally leads to diffusion of the hydrogen atom over the surface. Additionally, these adsorbed H-atoms can be used in reactions to form new molecules, such as CH4 and C2Hx, although this is dependent on the precise morphology of the surface. New molecules are also formed by subtraction of H-atoms from adsorbed radicals, leading to occasional formation of H2 and C2Hx molecules.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000309375700040 Publication Date 2012-09-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 37 Open Access
Notes Approved Most recent IF: 4.536; 2012 IF: 4.814
Call Number (up) UA @ lucian @ c:irua:101522 Serial 2640
Permanent link to this record
 
 
Author Aerts, R.; Martens, T.; Bogaerts, A.
Title Influence of vibrational states on CO2 splitting by dielectric barrier discharges Type A1 Journal article
Year 2012 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 116 Issue 44 Pages 23257-23273
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In this paper, the splitting of CO2 in a pulsed plasma system, such as a dielectric barrier discharge (DBD), is evaluated from a chemical point of view by means of numerical modeling. For this purpose, a chemical reaction set of CO2 in an atmospheric pressure plasma is developed, including the vibrational states of CO2, O2, and CO. The simulated pulses are matched to the conditions of a filament (or microdischarge) and repeated with intervals of 1 μs. The influence of vibrationally excited CO2 as well as other neutral species, ions, and electrons on the CO2 splitting is discussed. Our calculations predict that the electrons have the largest contribution to the CO2 splitting at the conditions under study, by electron impact dissociation. The contribution of vibrationally excited CO2 levels in the splitting of CO2 is found be 6.4%, when only considering one microdischarge pulse and its afterglow, but it can be much higher for consecutive discharge pulses, as is typical for a filamentary DBD, when the interpulse time is short enough and accumulation effects in the vibrationally excited CO2 densities can occur.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000310769300012 Publication Date 2012-10-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 112 Open Access
Notes Approved Most recent IF: 4.536; 2012 IF: 4.814
Call Number (up) UA @ lucian @ c:irua:101764 Serial 1659
Permanent link to this record
 
 
Author Li, M.R.; Retuerto, M.; Bok Go, Y.; Emge, T.J.; Croft, M.; Ignatov, A.; Ramanujachary, K.V.; Dachraoui, W.; Hadermann, J.; Tang, M.B.; Zhao, J.T.; Greenblatt, M.;
Title Synthesis, crystal structure, and properties of KSbO3-type Bi3Mn1.9Te1.1O11 Type A1 Journal article
Year 2013 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 197 Issue Pages 543-549
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Single crystals of Bi3Mn1.9Te1.1O11 were prepared from NaCl+KCl flux. This compound adopts KSbO3-type crystal structure as evidenced by electron and single crystal X-ray diffraction analysis. The three-dimensional channel structure is formed by corner-sharing octahedral (Mn0.63Te0.37)2O10 dimers and two identical (Bi1)4(Bi2)2 interpenetrating lattices. The intra-dimer Mn/TeMn/Te distances in Bi3Mn1.9Te1.1O11 are short and are consistent with weak metalmetal interactions. The mixed oxidation state of manganese and the edge-sharing octahedral features are confirmed by X-ray near edge absorption spectroscopy measurements, which indicate Bi3(MnIII1.1MnIV0.8)TeVI1.1O11 with 57.7% Mn3+ and 42.3% Mn4+. The partial substitution of Te for Mn perturbs long-range magnetic interactions, thereby destroying the ferromagnetic ordering found in Bi3Mn3O11 (TC=150 K).
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000312281000076 Publication Date 2012-07-25
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 13 Open Access
Notes Approved Most recent IF: 2.299; 2013 IF: 2.200
Call Number (up) UA @ lucian @ c:irua:101779 Serial 3452
Permanent link to this record
 
 
Author Saniz, R.; Xu, Y.; Matsubara, M.; Amini, M.N.; Dixit, H.; Lamoen, D.; Partoens, B.
Title A simplified approach to the band gap correction of defect formation energies : Al, Ga, and In-doped ZnO Type A1 Journal article
Year 2013 Publication The journal of physics and chemistry of solids Abbreviated Journal J Phys Chem Solids
Volume 74 Issue 1 Pages 45-50
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract The calculation of defect levels in semiconductors within a density functional theory approach suffers greatly from the band gap problem. We propose a band gap correction scheme that is based on the separation of energy differences in electron addition and relaxation energies. We show that it can predict defect levels with a reasonable accuracy, particularly in the case of defects with conduction band character, and yet is simple and computationally economical. We apply this method to ZnO doped with group III elements (Al, Ga, In). As expected from experiment, the results indicate that Zn substitutional doping is preferred over interstitial doping in Al, Ga, and In-doped ZnO, under both zinc-rich and oxygen-rich conditions. Further, all three dopants act as shallow donors, with the +1 charge state having the most advantageous formation energy. Also, doping effects on the electronic structure of ZnO are sufficiently mild so as to affect little the fundamental band gap and lowest conduction bands dispersion, which secures their n-type transparent conducting behavior. A comparison with the extrapolation method based on LDA+U calculations and with the HeydScuseriaErnzerhof hybrid functional (HSE) shows the reliability of the proposed scheme in predicting the thermodynamic transition levels in shallow donor systems.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000311062500009 Publication Date 2012-08-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3697; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.059 Times cited 36 Open Access
Notes Fwo; Bof-Nio Approved Most recent IF: 2.059; 2013 IF: 1.594
Call Number (up) UA @ lucian @ c:irua:101782 Serial 3004
Permanent link to this record
 
 
Author Sivek, J.; Leenaerts, O.; Partoens, B.; Peeters, F.M.
Title First-principles investigation of bilayer fluorographene Type A1 Journal article
Year 2012 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 116 Issue 36 Pages 19240-19245
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Ab initio calculations within the density functional theory formalism are performed to investigate the stability and electronic properties of fluorinated bilayer graphene (bilayer fluorographene). A comparison is made to previously investigated graphane, bilayer graphane, and fluorographene. Bilayer fluorographene is found to be a much more stable material than bilayer graphane. Its electronic band structure is similar to that of monolayer fluorographene, but its electronic band gap is significantly larger (about 1 eV). We also calculate the effective masses around the Gamma-point for fluorographene and bilayer fluorographene and find that they are isotropic, in contrast to earlier reports. Furthermore, it is found that bilayer fluorographene is almost as strong as graphene, as its 2D Young's modulus is approximately 300 N m(-1).
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000308631300022 Publication Date 2012-08-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 39 Open Access
Notes ; This work is supported by the ESF-Eurocores program EuroGRAPHENE (project CONERAN) and the Flemish Science Foundation (FWO-V1). ; Approved Most recent IF: 4.536; 2012 IF: 4.814
Call Number (up) UA @ lucian @ c:irua:101842 Serial 1211
Permanent link to this record
 
 
Author Hadermann, J.; Abakumov, A.; Van Rompaey, S.; Perkisas, T.; Filinchuk, Y.; Van Tendeloo, G.
Title Crystal structure of a lightweight borohydride from submicrometer crystallites by precession electron diffraction Type A1 Journal article
Year 2012 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 24 Issue 17 Pages 3401-3405
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We demonstrate that precession electron diffraction at low-dose conditions can be successfully applied for structure analysis of extremely electron-beam-sensitive materials. Using LiBH4 as a test material, complete structural information, including the location of the H atoms, was obtained from submicrometer-sized crystallites. This demonstrates for the first time that, where conventional transmission electron microscopy techniques fail, quantitative precession electron diffraction can provide structural information from submicrometer particles of such extremely electron-beam-sensitive materials as complex lightweight hydrides. We expect the precession electron diffraction technique to be a useful tool for nanoscale investigations of thermally unstable lightweight hydrogen-storage materials.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000308833400012 Publication Date 2012-08-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 17 Open Access
Notes Approved Most recent IF: 9.466; 2012 IF: 8.238
Call Number (up) UA @ lucian @ c:irua:101845 Serial 567
Permanent link to this record
 
 
Author Khalilov, U.; Pourtois, G.; van Duin, A.C.T.; Neyts, E.C.
Title On the c-Si\mid a-SiO2 interface in hyperthermal Si oxidation at room temperature Type A1 Journal article
Year 2012 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 116 Issue 41 Pages 21856-21863
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The exact structure and properties of the Si vertical bar SiO2 interface are very important in microelectronics and photovoltaic devices such as metal-oxide-semiconductor field-effect transistors (MOSFETs) and solar cells. Whereas Si vertical bar SiO2 structures are traditionally produced by thermal oxidation, hyperthermal oxidation shows a number of promising advantages. However, the Si vertical bar SiO2 interface induced in hyperthermal Si oxidation has not been properly investigated yet. Therefore, in this work, the interface morphology and interfacial stresses during hyperthermal oxidation at room temperature are studied using reactive molecular dynamics simulations based on the ReaxFF potential. Interface thickness and roughness, as well as the bond length and bond angle distributions in the interface are discussed and compared with other models developed for the interfaces induced by traditional thermal oxidation. The formation of a compressive stress is observed. This compressive stress, which at the interface amounts about 2 GPa, significantly slows down the inward silica growth. This value is close to the experimental value in the Si vertical bar SiO2 interface obtained in traditional thermal oxidation.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000309902100026 Publication Date 2012-09-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 27 Open Access
Notes Approved Most recent IF: 4.536; 2012 IF: 4.814
Call Number (up) UA @ lucian @ c:irua:102167 Serial 2458
Permanent link to this record
 
 
Author Charkin, D.O.; Urmanov, A.V.; Kazakov, S.M.; Batuk, D.; Abakumov, A.M.; Knöner, S.; Gati, E.; Wolf, B.; Lang, M.; Shevelkov, A.V.; Van Tendeloo, G.; Antipov, E.V.;
Title Synthesis, crystal structure, transport, and magnetic properties of novel ternary copper phosphides, A2Cu6P5(A = Sr, Eu) and EuCu4P3 Type A1 Journal article
Year 2012 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 51 Issue 16 Pages 8948-8955
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Three new ternary copper phosphides, Sr2Cu6P5, Eu2Cu6P5, and EuCu4P3, have been synthesized from the elements in evacuated silica capsules. Eu2Cu6P5 and Sr2Cu6P5 adopt the Ca2Cu6P5-type structure, while EuCu4P3 is isostructural to BaMg4Si3 and still remains the only representative of this structure type among the ternary Cu pnictides. All three materials show metallic conductivity in the temperature range 2 K <= T <= 290 K, with no indication for superconductivity. For Eu2Cu6P5 and EuCu4P3, long-range magnetic order was observed, governed by 4f local moments on the Eu atoms with predominant ferromagnetic interactions. While Eu2Cu6P5 shows a single ferromagnetic transition at T-C = 34 K, the magnetic behavior of EuCu4P3 is more complex, giving rise to three consecutive magnetic phase transitions at 70, 43, and 18 K.
Address
Corporate Author Thesis
Publisher Place of Publication Easton, Pa Editor
Language Wos 000307606200042 Publication Date 2012-07-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.857 Times cited 13 Open Access
Notes Approved Most recent IF: 4.857; 2012 IF: 4.593
Call Number (up) UA @ lucian @ c:irua:102217 Serial 3453
Permanent link to this record
 
 
Author Martin, J.M.L.; Taylor, P.R.; François, J.P.; Gijbels, R.
Title Ab initio study of the spectroscopy, kinetics, and thermochemistry of the BN2 molecule Type A1 Journal article
Year 1994 Publication Chemical physics letters Abbreviated Journal Chem Phys Lett
Volume 222 Issue Pages 517-523
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos A1994NN02600016 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.897 Times cited 14 Open Access
Notes Approved no
Call Number (up) UA @ lucian @ c:irua:10255 Serial 36
Permanent link to this record
 
 
Author Martin, J.M.L.; Taylor, P.R.; François, J.P.; Gijbels, R.
Title Ab initio study of the spectroscopy, kinetics, and thermochemistry of the C2N and CN2 molecules Type A1 Journal article
Year 1994 Publication Chemical physics letters Abbreviated Journal Chem Phys Lett
Volume 226 Issue 5/6 Pages 475-483
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Several structures and electronic states of the C2N and CN2 molecules have been studied using complete active space SCF (CASSCF), multireference configuration interaction (MRCI), and coupled cluster (CCSD(T)) methods. Both molecules are very stable. Our best computed total atomization energies SIGMAD(e) are 288.6 +/- 2 kcal/mol for CN2, and 294.1 +/- 2 kcal/mol for C2N. The CNC and CCN structures for C2N are nearly isoenergetic. CNN(3PI) lies about 30 kcal/mol above NCN(3PI(g)), but has a high barrier towards interconversion and is therefore observed experimentally. Computed harmonic frequencies for CNN are sensitive to the correlation treatment: they are reproduced well using multireference methods as well as the CCSD(T) method. High spin contamination has a detrimental effect on computed harmonic frequencies at the CCSD(T) level.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos A1994PE00500008 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.897 Times cited 46 Open Access
Notes Approved no
Call Number (up) UA @ lucian @ c:irua:10256 Serial 37
Permanent link to this record
 
 
Author Bittencourt, C.; Felten, A.; Douhard, B.; Colomer, J.-F.; Van Tendeloo, G.; Drube, W.; Ghijsen, J.; Pireaux, J.-J.
Title Metallic nanoparticles on plasma treated carbon nanotubes : $Nano2hybrids$ Type A1 Journal article
Year 2007 Publication Surface science : a journal devoted to the physics and chemistry of interfaces T2 – International Conference on NANO-Structures Self Assembling, JUL 02-06, 2006, Aix en Provence, FRANCE Abbreviated Journal Surf Sci
Volume 601 Issue 13 Pages 2800-2804
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Multi-wall carbon nanotubes (MWCNTs) were decorated with metal clusters by thermal evaporation. Transmission electron microscopy (TEM) shows that the nature and extent of metal coverage can be varied by plasma treating the MWCNT surface. The metal clusters on oxygen plasma treated arc-discharge MWCNTs have a more dense distribution than the clusters evaporated on as-synthesized are-discharge MWCNTs. In contrast, the plasma treatment did not affect the cluster distribution on CVD MWCNTs. Analyses of the valence band and the core levels by X-ray photoelectron spectroscopy suggest poor charge transfer between gold clusters and MWCNTs; on the contrary suggest good charge transfer between Ni clusters and MWCNTs. (c) 2007 Elsevier B. V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000248030100055 Publication Date 2006-12-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0039-6028; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.062 Times cited 44 Open Access
Notes Pai-V 1 Approved Most recent IF: 2.062; 2007 IF: 1.855
Call Number (up) UA @ lucian @ c:irua:102663 Serial 2011
Permanent link to this record
 
 
Author Aichele, T.; Robin, I.-C.; Bougerol, C.; André, R.; Tatarenko, S.; Van Tendeloo, G.
Title CdSe quantum dot formation induced by amorphous Se Type A1 Journal article
Year 2007 Publication Surface science : a journal devoted to the physics and chemistry of interfaces T2 – International Conference on NANO-Structures Self Assembling, JUL 02-06, 2006, Aix en Provence, FRANCE Abbreviated Journal Surf Sci
Volume 601 Issue 13 Pages 2664-2666
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The mechanism allowing the transition from a two-dimensional strained layer of CdSe on ZnSe to self-assembled islands induced by the use of amorphous selenium is still not fully understood. For a better understanding, atomic force microscopy and transmission electron microscopy studies were performed on CdSe films with a thickness close to that for quantum dot formation. Below this thickness, the sample surface results in undulations along the [110] crystal direction, while few quantum dots are situated in the wave valleys. Plan view transmission electron microscopy studies reveal a strong anisotropy of the islands and show that the Se desorption conditions are crucial. (C) 2006 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000248030100027 Publication Date 2006-12-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0039-6028; ISBN Additional Links UA library record; WoS full record
Impact Factor 2.062 Times cited Open Access
Notes Approved Most recent IF: 2.062; 2007 IF: 1.855
Call Number (up) UA @ lucian @ c:irua:102668 Serial 304
Permanent link to this record
 
 
Author Thomé, T.; Colaux, J.L.; Colomer, J.-F.; Bertoni, G.; Terwagne, G.
Title Formation of carbon nitride nanospheres by ion implantation Type A1 Journal article
Year 2007 Publication Materials chemistry and physics Abbreviated Journal Mater Chem Phys
Volume 103 Issue 2-3 Pages 290-294
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Carbon nitride nanospheres have been synthesized into copper by simultaneous high fluence (10(18) at. cm(-2)) implantations of C-12 and N-15 ions. The composition of the implanted region has been measured using C-12(d,p(0))C-13 and N-15(d,alpha(0))C-13 nuclear reactions induced by a 1.05 MeV deuteron beam. The C-12 and N-15 depth profiles are very close and the retained doses into copper are relatively high, which indicates that carbon and nitrogen diffusion processes are likely limited during implantation. High resolution transmission electron microscopy (HRTEM) observations and electron diffraction (ED) analyses have been carried out to determine the structure of the nanospheres formed during implantation. Some consist in small hollow amorphous nanocapsules with sizes ranging from 30 to 100 nm. Large gas bubbles with diameters up to 300 mn have also been observed in the copper matrix. Electron energy-loss spectroscopy (EELS) measurements performed on the small nanocapsules indicate that their shells are composed of carbon and nitrogen. (c) 2007 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos 000247715300016 Publication Date 2007-02-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0254-0584; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.084 Times cited 1 Open Access
Notes Approved Most recent IF: 2.084; 2007 IF: 1.871
Call Number (up) UA @ lucian @ c:irua:102670 Serial 1258
Permanent link to this record
 
 
Author Nikolaev, A.V.; Michel, K.H.
Title Superexchange and electron correlations in alkali fullerides AC60, A=K, Rb, Cs Type A1 Journal article
Year 2005 Publication The journal of chemical physics Abbreviated Journal J Chem Phys
Volume 122 Issue 6 Pages 064310-64314
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Superexchange interactions in alkali fullerides AC(60) are derived for C-60 molecular ions separated by interstitial alkali-metal ions. We use a multiconfiguration approach which comprises the lowest molecular orbital states of the C-60 molecule and the excited s and d states of the alkali-metal atom A. Interactions are described by the valence bond (Heitler-London) method for a complex (C-60 – A – C-60) – with two valence electrons. The electronic charge transfer between the alkali-metal atom and a neighboring C-60 molecule is not complete. The occupation probability of excited d and s states of the alkali atom is not negligible. In correspondence with the relative positions of the C-60 molecules and A atoms in the polymer crystal, we consider 180degrees and 90degrees (angle) superexchange pathways. For the former case the ground state is found to be a spin singlet separated from a triplet at similar to20 K. For T < 20 K there appear strong spin correlations for the 180degrees superexchange pathway. The results are related to spin lattice relaxation experiments on CsC60 in the polymerized and in the quenched cubic phase. (C) 2005 American Institute of Physics.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000226918100018 Publication Date 2005-02-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9606; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.965 Times cited 11 Open Access
Notes Approved Most recent IF: 2.965; 2005 IF: 3.138
Call Number (up) UA @ lucian @ c:irua:102740 Serial 3377
Permanent link to this record
 
 
Author Antipov, E.V.; Khasanova, N.R.; Pshirkov, J.S.; Putilin, S.N.; Bougerof, C.; Lebedev, O.I.; Van Tendeloo, G.; Baranov, A.; Park, Y.W.
Title The superconducting bismuth-based mixed oxides Type A1 Journal article
Year 2003 Publication Journal of low temperature physics T2 – International Conference on Physics and Chemistry of Molecular and Oxide, Superconductors (MOS2002), AUG 13-18, 2002, HSINCHU, TAIWAN Abbreviated Journal J Low Temp Phys
Volume 131 Issue 3-4 Pages 575-587
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The present paper describes the synthesis, characterization of mixed-valence bismuthates with 3- or 2-dimensional perovskite-like structures and structural criteria that influence superconductivity in these compounds. Single-phase samples of Sr1-xKxBiO3 were prepared for the broad range of K-content: 0.25 less than or equal to x less than or equal to 0.65. For these bismuthates the symmetry of the structure changes from monoclinic to orthorhombic and finally to tetragonal upon increasing the K-content thus resulting in the decrease of the Bi-O distances and reduction of the network distortions. Superconductivity with maximum T-c = 12K exists in the narrow range (x approximate to 0.5 – 0.6) within the stability field of the tetragonal phase (0.33 less than or equal to x less than or equal to 0.65), when the 3-dimensional octahedral framework has close to the ideal perovskite structure arrangement. At the same time compositions with close to optimal Bi-valence (x = 0.33 and 0.43) do not show any sign of superconductivity, probably, due to structural distortions. The layered type (BaK)(3)Bi2O7 and (Ba,K)(2)BiO4 bismuthates belonging to the A(n+1)B(n)O(3n+1) homologous series were investigated Buckling of the (BiO2) layers in the structure of the n = 2 member was revealed The formation of the n=1 bismuthate was found by Electron Microscopy and X-ray powder diffraction studies. Both types of compounds are considered to be possible candidates for new superconducting materials among bismuthates.
Address
Corporate Author Thesis
Publisher Place of Publication New York Editor
Language Wos 000181768000061 Publication Date 2003-04-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2291; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.3 Times cited 3 Open Access
Notes Approved Most recent IF: 1.3; 2003 IF: 1.171
Call Number (up) UA @ lucian @ c:irua:102803 Serial 3597
Permanent link to this record
 
 
Author Piedigrosso, P.; Konya, Z.; Colomer, J.-F.; Fonseca, A.; Van Tendeloo, G.; Nagy, J.B.
Title Production of differently shaped multi-wall carbon nanotubes using various cobalt supported catalysts Type A1 Journal article
Year 2000 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 2 Issue 1 Pages 163-170
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Catalytic synthesis and transmission electron microscopy (TEM) of multi-wall carbon nanotubes are presented. Silica, zeolite and alumina supported cobalt catalysts were prepared by different methods (impregnation and ion-adsorption precipitation) and were used to produce nanotubes. The synthesis was carried out in a fixed bed flow reactor and the process was optimized in order to produce carbon nanotubes on a gram scale. The influence of various parameters such as the method of catalyst preparation, the nature of the support, cobalt concentration and reaction conditions on the formation of nanotubes was investigated. The carbon deposits were measured and the quality of nanotubes was determined by low and high resolution TEM. Multi-wall straight and coiled nanotubes were found to be fairly regular with an average inner (outer) diameter of 4-7 nm (8-23 nm) and with lengths up to 0.1 mm.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000084333800025 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076;1463-9084; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.123 Times cited 53 Open Access
Notes Approved Most recent IF: 4.123; 2000 IF: 1.653
Call Number (up) UA @ lucian @ c:irua:102889 Serial 2723
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Author Krekels, T.; Milat, O.; Van Tendeloo, G.; Amelinckx, S.; Babu, T.G.N.; Wright, A.J.; Greaves, C.
Title Order and disorder in (Nd,Ce)nO2nSr2GaCu2O5 and YSr2CoCu2O7 Type A1 Journal article
Year 1993 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 105 Issue 2 Pages 313-335
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos A1993LT32700002 Publication Date 2002-10-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.133 Times cited 50 Open Access
Notes Approved no
Call Number (up) UA @ lucian @ c:irua:102965 Serial 2499
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Author Milat, O.; Van Tendeloo, G.; Amelinckx, S.; Babu, T.G.N.; Greaves, C.
Title Structural variants of Ca0.85CuO2(Ca5+xCu6O12) Type A1 Journal article
Year 1992 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 101 Issue 1 Pages 92-114
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The structure of Ca0.85CuO2 was reexamined by means of electron diffraction and electron microscopy using the newly developed method of selective imaging in intergrowth structures in which the two substructures are based on different sublattices. The results of previous work are confirmed. Moreover, it is shown that two stacking variants and their twin related structures occur in the calcium substructure. The copper-oxygen substructure occurs in one variant only; it is often modulated by the various calcium arrangements, leading to phase disorder in its modulation pattern. It is shown that the ribbons of CuO4 clusters are presumably tilted with respect to the (010) plane.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos A1992JW94200012 Publication Date 2006-06-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.133 Times cited 10 Open Access
Notes Approved
Call Number (up) UA @ lucian @ c:irua:103021 Serial 3272
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Author Milat, O.; Van Tendeloo, G.; Amelinckx, S.; Babu, T.G.N.; Greaves, C.
Title The modulated structure of Ca.85CuO2 as studied by means of electron diffraction and microscopy Type A1 Journal article
Year 1992 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 97 Issue 2 Pages 405-418
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos A1992HL68700019 Publication Date 2003-12-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.133 Times cited 15 Open Access
Notes Approved PHYSICS, APPLIED 47/145 Q2 #
Call Number (up) UA @ lucian @ c:irua:103042 Serial 3590
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Author Helm, M.; Peeters, F.M.; de Rosa, F.; Colas, E.; Harbison, J.P.; Florez, L.T.
Title Infrared-spectroscopy of subbands, minibands, and donors in GaAs/AlGaAs superlattices Type A1 Journal article
Year 1992 Publication Surface science : a journal devoted to the physics and chemistry of interfaces T2 – 9TH INTERNATIONAL CONF ON THE ELECTRONIC PROPERTIES OF TWO-DIMENSIONAL, SYSTEMS ( EP2DS-9 ) / 5TH INTERNATIONAL CONF ON MODULATED SEMICONDUCTOR, STRUCTURES ( MSS-5 ), JUL Abbreviated Journal Surf Sci
Volume 263 Issue 1-3 Pages 518-526
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract A far-infrared absorption study of electrons in lightly-doped GaAs/Al0.3Ga0.7As superlattices is presented. Both weakly and strongly coupled superlattices are investigated, and the difference between intersubband transitions and transitions between extended minibands is demonstrated. At low temperatures, the absorption spectra are dominated by donor transitions. The 1s-2p(z) transition, which is intimately related to the intersubband transition, is observed. All experimental data are compared to an envelope function calculation for the miniband structure and a variational calculation for the donor energies. Excellent agreement between experiment and theory is achieved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos A1992HF18600104 Publication Date 2002-10-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0039-6028; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.925 Times cited 5 Open Access
Notes Approved no
Call Number (up) UA @ lucian @ c:irua:103055 Serial 1665
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Author Recham, N.; Casas-Cabanas, M.; Cabana, J.; Grey, C.P.; Jumas, J.-C.; Dupont, L.; Armand, M.; Tarascon, J.-M.
Title Formation of a complete solid solution between the triphylite and fayalite olivine structures Type A1 Journal article
Year 2008 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 20 Issue 21 Pages 6798-6809
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The recent infatuation for LiFePO4 as positive electrode material in Li-ion batteries has prompted a renewed interest in olivine-type structures, with a view to enhance their conduction proper-ties. We show that the dual substitution of Li for Fe and of P for Si in the olivine LiFePO4 phase leads to a complete solid solution Li1-xFe1+xP1-xSixO4 as deduced from combined X-ray diffraction, Mossbauer, and NMR experiments. Our findings challenge the common belief that the anionic network cannot be substituted. Moreover. it is found that such a substitution promotes Li intersite mixing between the olivine M1 and M2 sites. Such mixing, together with the worsening of the conducting properties of the dually substituted samples, is believed to be responsible for the poor electrochemical performances of the member's series. Beyond x = 0.20, the samples were electrochemically inactive. While the current materials are disappointing application-wise, such a study provides clues to the rich chemistry remaining to be unveiled with olivine-type structures in particular and polyanionic compounds in general.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000260658100036 Publication Date 2008-10-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 35 Open Access
Notes Approved Most recent IF: 9.466; 2008 IF: 5.046
Call Number (up) UA @ lucian @ c:irua:103082 Serial 1255
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Author Mueller, G.; Stahnke, F.; Bleiner, D.
Title Fast steel-cleanness characterization by means of laser-assisted plasma spectrometric methods Type A1 Journal article
Year 2006 Publication Talanta : the international journal of pure and applied analytical chemistry T2 – 34th Colloquium Spectroscopicum Internationale, SEP 04-09, 2005, Univ Antwerp, Antwerp, BELGIUM Abbreviated Journal Talanta
Volume Issue Pages
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Laser-assisted plasma spectrometry is a palette of analytical techniques (L-OES, LA-ICP-MS) capable of fast spatially-resolved elemental analysis in the micrometer range. For fast estimation of the occurrence in steel samples of non-metallic inclusions, which degrade the material's technical properties, simultaneous OES detection and sequential ICP-MS detection were compared. Histograms were obtained for the intensity distribution of the acquired signals (laser pulse statistics). The skewness coefficient of the histograms for Al (indicator of non-metallic inclusions) was found to be clearly dependent on the fraction of non-metallic inclusions in the case of scanning L-OES. For LA-ICP-MS less clear dependence was observed, which was influenced by the acquisition characteristics. In fact, less measurement throughput limited for LA-ICP-MS the counting statistics to an extent that overrides the benefit of higher detection power as compared to L-OES. (c) 2006 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Pergamon Place of Publication Oxford Editor
Language Wos 000242871900015 Publication Date 2006-07-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0039-9140; 1873-3573 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.162 Times cited 12 Open Access
Notes Approved Most recent IF: 4.162; 2006 IF: 2.810
Call Number (up) UA @ lucian @ c:irua:103122 Serial 4518
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Author Kirschhock, C.E.A.; Liang, D.; Aerts, A.; Aerts, C.A.; Kremer, S.P.B.; Jacobs, P.A.; Van Tendeloo, G.; Martens, J.A.
Title On the TEM and AFM evidence of zeosil nanoslabs present during the synthesis of silicalite-1 : reply Type L1 Letter to the editor
Year 2004 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit
Volume 43 Issue 35 Pages 4562-4564
Keywords L1 Letter to the editor; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000224008400003 Publication Date 2004-08-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-7851;1521-3773; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 11.994 Times cited Open Access
Notes Fwo; Iap-Pai Approved Most recent IF: 11.994; 2004 IF: 9.161
Call Number (up) UA @ lucian @ c:irua:103253 Serial 2457
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Author Linssen, T.; Cassiers, K.; Cool, P.; Lebedev, O.; Whittaker, A.; Vansant, E.F.
Title Physicochemical and structural characterization of mesoporous aluminosilicates synthesized from leached saponite with additional aluminum incorporation Type A1 Journal article
Year 2003 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 15 Issue 25 Pages 4863-4873
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Abstract A thorough investigation was performed on the physical (mechanical, thermal, and hydrothermal stability) and chemical (ion exchange capacity and silanol number) characteristics of aluminosilicate FSMs, synthesized via a new successful short-time synthesis route using leached saponite and a low concentration of CTAB. Moreover, the influence of an additional Al incorporation, utilizing different aluminum sources, on the structure of the FSM derived from saponite is studied. A mesoporous aluminosilicate with a low Si/Al ratio of 12.8 is synthesized, and still has a very large surface area of 1130 m(2)/g and pore volume of 0.92 cm(3)/g. The aluminum-containing samples all have a high cation exchange capacity of around 1 mmol/9 while they still have a silanol number of about 0.9 OH/nm(2); both characteristics being interesting for high-yield postsynthesis modification reactions. Finally, a study is performed on the transformation of the aluminosilicates into their Bronsted acid form via the exchange with ammonium ions and a consecutive heat treatment.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000187250800026 Publication Date 2003-12-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 11 Open Access
Notes Approved Most recent IF: 9.466; 2003 IF: 4.374
Call Number (up) UA @ lucian @ c:irua:103265 Serial 2618
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Author Lazoryak, B.I.; Baryshnikova, O.V.; Stefanovich, S.Y.; Malakho, A.P.; Morozov, V.A.; Belik, A.A.; Leonidov, I.A.; Leonidova, O.N.; Van Tendeloo, G.
Title Ferroelectric and ionic-conductive properties of nonlinear-optical vanadate, Ca9Bi(VO4)7 Type A1 Journal article
Year 2003 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 15 Issue 15 Pages 3003-3010
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Structural, chemical, and physical properties of whitlockite-type Ca9Bi(VO4)(7) were studied by X-ray powder diffraction (XRD), electron diffraction (ED), second-harmonic generation (SHG), thermogravimetry, differential scanning calorimetry, dielectric, and electrical-conductivity measurements. A new phase-transition of the ferroelectric type was found in Ca9Bi(VO4)(7) with a transition temperature, T-c of 1053 +/- 3 K. The polar phase, beta-Ca9Bi(VO4)(7), is stable below T-c down to at least 160 K. The centrosymmetric beta'-phase is stable above T-c up to 1273 +/- 5 K. Above 1273 K, it decomposes to give BiVO4 and whitlockite-type solid solutions of Ca9+1.5xBi1-x(VO4)(7). The beta<---->beta' phase transition is reversible and of second order. Electrical conductivity of beta'-Ca9Bi(VO4)(7) is rather high (sigma = 0.6 x 10(-3) S/cm at 1200 K) and obeys the Arrhenius law with an activation energy of 1.0 eV. Structure parameters of Ca9Bi(VO4)(7) are refined by the Rietveld method from XRD data measured at room temperature (space group R3c; Z = 6; a = 10.8992(1) Angstrom, c = 38.1192(4) Angstrom, and V = 3921.6(1) Angstrom(3); R-wp = 3.06% and R-p = 2.36%). Bi3+ ions together with Ca2+ ions are statistically distributed among the M1, M2, M3, and M5 sites. Ca9Bi(VO4)(7) has a SHG efficiency of about 140 times that of quartz. Through the powder SHG measurements, we estimated the nonlinear optical susceptibility, Digital, at about 6.1-7.2 pm/V. This value for Ca9Bi(VO4)(7) is comparable with that for known nonlinear optical materials such as LiNbO3 and LiTaO3.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000184379900024 Publication Date 2003-07-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 51 Open Access
Notes Iup V-1; Dwtc Approved Most recent IF: 9.466; 2003 IF: 4.374
Call Number (up) UA @ lucian @ c:irua:103284 Serial 1179
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Author Cassiers, K.; van der Voort, P.; Linssen, T.; Vansant, E.F.; Lebedev, O.; van Landuyt, J.
Title A counterion-catalyzed (S0H+)(X-I+) pathway toward heat- and steam-stable mesostructured silica assembled from amines in acidic conditions Type A1 Journal article
Year 2003 Publication The journal of physical chemistry : B : condensed matter, materials, surfaces, interfaces and biophysical Abbreviated Journal J Phys Chem B
Volume 107 Issue 16 Pages 3690-3696
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Abstract An alternative pathway to assemble mesoporous molecular sieve silicas is developed using nonionic alkylamines and N,N-dimethylalkylamines (SO) as structure-directing agents in acidic conditions. The synthesized mesostructures possess wormhole-like frameworks with pore sizes and pore volumes in the range of 20-90 Angstrom and 0.5-1.3 cm(3)/g, respectively. The formation of the mesophase is controlled by a counterion-mediated mechanism of the type (S(0)H(+))(X(-)I(+)), where S(0)H(+) are protonated water molecules that are hydrogen bonded to the lone electron pairs on the amine surfactant headgroups (S(0)H(+)), X(-) is the counteranion originating from the acid, and I(+) are the positively charged (protonated) silicate species. We found that the stronger the ion X(-) is bonded to S(0)H(+), the more it catalyzes the silica condensation into (S(0)H(+))(X(-)I(+)). Br(-) is shown to be a strong binding anion and therefore a fast silica polymerization promoter compared to Cl(-) resulting in the formation of a higher quality mesophase for the Br(-) syntheses. We also showed that the polymerization rate of the silica, dictated by the counterion, controls the morphology of the mesostructures from nonuniform agglomerated blocks in the case of Br(-) syntheses to spherical particles for the Cl(-) syntheses. Next to many benefits such as low temperature, short synthesis time, and the use of inexpensive, nontoxic, and easily extractable amine templates, the developed materials have a remarkable higher thermal and hydrothermal stability compared to hexagonal mesoporous silica, which is also prepared with nonionic amines but formed through the S(0)I(0) mechanism.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000182350200005 Publication Date 2003-04-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1520-6106;1520-5207; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.177 Times cited 9 Open Access
Notes Approved Most recent IF: 3.177; 2003 IF: 3.679
Call Number (up) UA @ lucian @ c:irua:103300 Serial 24
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Author Verberck, B.; Michel, K.H.; Nikolaev, A.V.
Title Crystal structures of polymerized fullerides AC60, A=K, Rb, Cs, and alkali-mediated interactions Type A1 Journal article
Year 2002 Publication The journal of chemical physics Abbreviated Journal J Chem Phys
Volume 116 Issue 23 Pages 10462-10474
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Starting from a model of rigid interacting C-60 polymer chains on an orthorhombic lattice, we study the mutual orientation of the chains and the stability of the crystalline structures Pmnn and I2/m. We take into account (i) van der Waals interactions and electric quadrupole interactions between C-60 monomers on different chains as well as (ii) interactions of the monomers with the surrounding alkali atoms. The direct interactions (i) always lead to an antiferrorotational structure Pmnn with alternate orientation of the C-60 chains in planes (001). The interactions (ii) with the alkalis consist of two parts: translation-rotation (TR) coupling where the orientations of the chains interact with displacements of the alkalis, and quadrupolar electronic polarizability (ep) coupling, where the electric quadrupoles on the C-60 monomers interact with induced quadrupoles due to excited electronic d-states of the alkalis. Both interactions (ii) lead to an effective orientation-orientation interaction between the C-60 chains and always favor the ferrorotational structure I2/m, where C-60 chains have a same orientation. The structures Pmnn for KC60 and I2/m for Rb- and CsC60 are the result of a competition between the direct interaction (i) and the alkali-mediated interactions (ii). In Rb- and CsC60 the latter are found to be dominant, the preponderant role being played by the quadrupolar electronic polarizability of the alkali ions. (C) 2002 American Institute of Physics.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000175905800044 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9606; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.965 Times cited 12 Open Access
Notes Approved Most recent IF: 2.965; 2002 IF: 2.998
Call Number (up) UA @ lucian @ c:irua:103350 Serial 578
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Author Stuer, C.; van Landuyt, J.; Bender, H.; de Wolf, I.; Rooyackers, R.; Badenes, G.
Title Investigation by convergent beam electron diffraction of the stress around shallow trench isolation structures Type A1 Journal article
Year 2001 Publication Journal of the electrochemical society Abbreviated Journal J Electrochem Soc
Volume 148 Issue 11 Pages G597-G601
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Convergent beam electron diffraction (CBED) is used in this study to investigate the stress distribution around shallow trench isolation (STI) structures. Attention is given to the influence of the different processing parameters and the width and spacing of the structures. The use of a wet or a dry pregate oxidation is found to have a strong influence on the stress behavior. Isolated lines show more stress, leading to the formation of defects in the silicon substrate if a wet pregate oxidation is used. The CBED analyses are compared with micro-Raman and bright-field transmission electron microscopy measurements. (C) 2001 The Electrochemical Society.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000171653100038 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4651; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.259 Times cited 13 Open Access
Notes Approved Most recent IF: 3.259; 2001 IF: 2.033
Call Number (up) UA @ lucian @ c:irua:103394 Serial 1725
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Author Van Tendeloo, G.; Garlea, O.; Darie, C.; Bougerol-Chaillout, C.; Bordet, P.
Title The fine structure of YCuO2+x delafossite determined by synchrotron powder diffraction and electron microscopy Type A1 Journal article
Year 2001 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 156 Issue 2 Pages 428-436
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract YCuO2 delafossite crystallizes into two stacking variants; hexagonal 2H or rhombohedral 3R, depending on the preparation conditions. The structure of the fully oxygenated material YCuO2.50 has been determined as orthorhombic (a(O) = 6.1961 Angstrom; b(O) = 11.2158 Angstrom; c(O) = 7.1505 Angstrom; space group Pnma). The structure is based on the hexagonal 2H structure (a(O) = a(H)root3; b(O) = c(H); c(O) = 2a(H)). Upon incomplete oxidation, a different YCuOZ phase with ideal composition YCuO2.33 and lattice parameters a(H root)3, a(H)root3, c(H) is also formed. Diffraction patterns are often very complex because of the presence of planar defects and intergrowth of both phases. Under electron beam irradiation, oxygen is released from the structure and one phase gradually transforms into the other. (C) 2001 Academic Press.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000167252000025 Publication Date 2002-09-18
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 33 Open Access
Notes Approved Most recent IF: 2.299; 2001 IF: 1.614
Call Number (up) UA @ lucian @ c:irua:103425 Serial 3581
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