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Author Zhang, Z.; Lobato, I.; Brown, H.; Jannis, D.; Verbeeck, J.; Van Aert, S.; Nellist, P. doi  openurl
  Title Generalised oscillator strength for core-shell electron excitation by fast electrons based on Dirac solutions Type Dataset
  Year 2023 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords Dataset; Electron microscopy for materials research (EMAT)  
  Abstract Inelastic excitation as exploited in Electron Energy Loss Spectroscopy (EELS) contains a rich source of information that is revealed in the scattering process. To accurately quantify core-loss EELS, it is common practice to fit the observed spectrum with scattering cross-sections calculated using experimental parameters and a Generalized Oscillator Strength (GOS) database [1].   The GOS is computed using Fermi’s Golden Rule and orbitals of bound and excited states. Previously, the GOS was based on Hartree-Fock solutions [2], but more recently Density Functional Theory (DFT) has been used [3]. In this work, we have chosen to use the Dirac equation to incorporate relativistic effects and have performed calculations using Flexible Atomic Code (FAC) [4]. This repository contains a tabulated GOS database based on Dirac solutions for computing double differential cross-sections under experimental conditions.   We hope the Dirac-based GOS database can benefit the EELS community for both academic use and industry integration.   Database Details: – Covers all elements (Z: 1-108) and all edges – Large energy range: 0.01 – 4000 eV – Large momentum range: 0.05 -50 Å-1 – Fine log sampling: 128 points for energy and 256 points for momentum – Data format: GOSH [3]   Calculation Details: – Single atoms only; solid-state effects are not considered – Unoccupied states before continuum states of ionization are not considered; no fine structure – Plane Wave Born Approximation – Frozen Core Approximation is employed; electrostatic potential remains unchanged for orthogonal states when – core-shell electron is excited – Self-consistent Dirac–Fock–Slater iteration is used for Dirac calculations; Local Density Approximation is assumed for electron exchange interactions; continuum states are normalized against asymptotic form at large distances – Both large and small component contributions of Dirac solutions are included in GOS – Final state contributions are included until the contribution of the previous three states falls below 0.1%. A convergence log is provided for reference.   Version 1.1 release note: – Update to be consistent with GOSH data format [3], all the edges are now within a single hdf5 file. A notable change in particular, the sampling in momentum is in 1/m, instead of previously in 1/Å. Great thanks to Gulio Guzzinati for his suggestions and sending conversion script.  Version 1.2 release note: – Add “File Type / File version” information [1] Verbeeck, J., and S. Van Aert. Ultramicroscopy 101.2-4 (2004): 207-224. [2] Leapman, R. D., P. Rez, and D. F. Mayers. The Journal of Chemical Physics 72.2 (1980): 1232-1243. [3] Segger, L, Guzzinati, G, & Kohl, H. Zenodo (2023). doi:10.5281/zenodo.7645765 [4] Gu, M. F. Canadian Journal of Physics 86(5) (2008): 675-689.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access Not_Open_Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:203392 Serial 9042  
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Author Grünewald, L.; Chezganov, D.; De Meyer, R.; Orekhov, A.; Van Aert, S.; Bogaerts, A.; Bals, S.; Verbeeck, J. doi  openurl
  Title Supplementary Information for “In-situ Plasma Studies using a Direct Current Microplasma in a Scanning Electron Microscope” Type Dataset
  Year 2023 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords Dataset; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Supplementary information for the article “In-situ Plasma Studies using a Direct Current Microplasma in a Scanning Electron Microscope” containing the videos of in-situ SEM imaging (mp4 files), raw data/images, and Jupyter notebooks (ipynb files) for data treatment and plots. Link to the preprint: https://doi.org/10.48550/arXiv.2308.15123 Explanation of the data files can be found in the Information.pdf file. The Videos folder contains the in-situ SEM image series mentioned in the paper. If there are any questions/bugs, feel free to contact me at lukas.grunewaldatuantwerpen.be  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access Not_Open_Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:203389 Serial 9100  
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Author Schryvers, D.; Shi, H.; Martinez, G.T.; Van Aert, S.; Frenzel, J.; Van Humbeeck, J. pdf  doi
openurl 
  Title Nano- and microcrystal investigations of precipitates, interfaces and strain fields in Ni-Ti-Nb by various TEM techniques Type P1 Proceeding
  Year 2013 Publication Materials science forum T2 – 9th European Symposium on Martensitic Transformations (ESOMAT 2012), SEP 09-16, 2012, St Petersburg, RUSSIA Abbreviated Journal  
  Volume 738/739 Issue Pages 65-71  
  Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)  
  Abstract In the present contribution several advanced electron microscopy techniques are employed in order to describe chemical and structural features of the nano- and microstructure of a Ni45.5Ti45.5Nb9 alloy. A line-up of Nb-rich nano-precipitates is found in the Ni-Ti-rich austenite of as-cast material. Concentration changes of the matrix after annealing are correlated with changes in the transformation temperatures. The formation of rows and plates of larger Nb-rich precipitates and particles is described. The interaction of a twinned martensite plate with a Nb-rich nano-precipitate is discussed and the substitution of Nb atoms on the Ti-sublattice in the matrix is confirmed.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lausanne Editor  
  Language Wos 000316089000011 Publication Date 2013-03-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1662-9752; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 2 Open Access  
  Notes Fwo Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:104692 Serial 2247  
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Author van Dyck, D.; Van Aert, S.; Croitoru, M. pdf  doi
openurl 
  Title Atomic resolution electron tomography: a dream? Type A1 Journal article
  Year 2006 Publication International journal of materials research Abbreviated Journal Int J Mater Res  
  Volume 97 Issue 7 Pages 872-879  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Vision lab  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000239916700003 Publication Date 2013-12-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1862-5282;2195-8556; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 0.681 Times cited 6 Open Access  
  Notes Approved Most recent IF: 0.681; 2006 IF: NA  
  Call Number UA @ lucian @ c:irua:60965 Serial 176  
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Author Van Aert, S.; den Dekker, A.J.; van den Bos, A.; van Dyck, D. doi  openurl
  Title High-resolution electron microscopy : from imaging toward measuring Type A1 Journal article
  Year 2002 Publication IEEE transactions on instrumentation and measurement Abbreviated Journal Ieee T Instrum Meas  
  Volume 51 Issue 4 Pages 611-615  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000178992000010 Publication Date 2003-01-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0018-9456; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.456 Times cited 13 Open Access  
  Notes Approved Most recent IF: 2.456; 2002 IF: 0.592  
  Call Number UA @ lucian @ c:irua:47521 Serial 1450  
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Author Van Aert, S.; den Dekker, A.J.; van den Bos, A.; Van Dyck, D. doi  isbn
openurl 
  Title High resolution electron microscopy from imaging towards measuring Type H2 Book chapter
  Year 2001 Publication ... IEEE International Instrumentation and Measurement Technology Conference T2 – Rediscovering measurement in the age of informatics : proceedings of the 18th IEEE Instrumentation and Measurement Technology Conference (IMTC), 2001: vol 3 Abbreviated Journal  
  Volume Issue Pages 2081-2086  
  Keywords H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Ieee Place of Publication Editor  
  Language Wos Publication Date 2002-11-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 0-7803-6646-8 Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:136870 Serial 4501  
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Author Boschker, H.; Huijben, M.; Vailinois, A.; Verbeeck, J.; Van Aert, S.; Luysberg, M.; Bals, S.; Van Tendeloo, G.; Houwman, E.P.; Koster, G.; Blank, D.H.A.; Rijnders, G. pdf  doi
openurl 
  Title Optimized fabrication of high-quality La0.67Sr0.33MnO3 thin films considering all essential characteristics Type A1 Journal article
  Year 2011 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys  
  Volume 44 Issue 20 Pages 205001-205001,9  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract In this paper, an overview of the fabrication and properties of high-quality La0.67Sr0.33MnO3 (LSMO) thin films is given. A high-quality LSMO film combines a smooth surface morphology with a large magnetization and a small residual resistivity, while avoiding precipitates and surface segregation. In the literature, typically only a few of these issues are adressed. We therefore present a thorough characterization of our films, which were grown by pulsed laser deposition. The films were characterized with reflection high energy electron diffraction, atomic force microscopy, x-ray diffraction, magnetization and transport measurements, x-ray photoelectron spectroscopy and scanning transmission electron microscopy. The films have a saturation magnetization of 4.0 µB/Mn, a Curie temperature of 350 K and a residual resistivity of 60 µΩ cm. These results indicate that high-quality films, combining both large magnetization and small residual resistivity, were realized. A comparison between different samples presented in the literature shows that focussing on a single property is insufficient for the optimization of the deposition process. For high-quality films, all properties have to be adressed. For LSMO devices, the thin-film quality is crucial for the device performance. Therefore, this research is important for the application of LSMO in devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000290150900001 Publication Date 2011-04-29  
  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 99 Open Access  
  Notes This research was financially supported by the Dutch Science Foundation, by NanoNed, a nanotechnology program of the Dutch Ministry of Economic Affairs, and by the NanOxide program of the European Science Foundation. This work is supported in part by the Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering, under contract DE-AC02-76SF00515. Approved Most recent IF: 2.588; 2011 IF: 2.544  
  Call Number UA @ lucian @ c:irua:89557UA @ admin @ c:irua:89557 Serial 2491  
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Author Van Aert, S.; van Dyck, D. pdf  doi
openurl 
  Title Do smaller probes in a scanning transmission electron microscope result in more precise measurement of the distances between atom columns? Type A1 Journal article
  Year 2001 Publication Philosophical magazine: B: physics of condensed matter: electronic, optical and magnetic properties Abbreviated Journal  
  Volume 81 Issue 11 Pages 1833-1846  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000172199700016 Publication Date 2007-07-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1364-2812;1463-6417; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 11 Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:47519 Serial 744  
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Author Van Aert, S.; Turner, S.; Delville, R.; Schryvers, D.; Van Tendeloo, G.; Ding, X.; Salje, E.K.H. pdf  doi
openurl 
  Title Functional twin boundaries Type A1 Journal article
  Year 2013 Publication Phase transitions Abbreviated Journal Phase Transit  
  Volume 86 Issue 11 Pages 1052-1059  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Functional interfaces are at the core of research in the emerging field of domain boundary engineering where polar, conducting, chiral, and other interfaces and twin boundaries have been discovered. Ferroelectricity was found in twin walls of paraelectric CaTiO3. We show that the effect of functional interfaces can be optimized if the number of twin boundaries is increased in densely twinned materials. Such materials can be produced by shear in the ferroelastic phase rather than by rapid quench from the paraelastic phase.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York Editor  
  Language Wos 000327475900002 Publication Date 2013-01-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0141-1594;1029-0338; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.06 Times cited 5 Open Access  
  Notes Approved Most recent IF: 1.06; 2013 IF: 1.044  
  Call Number UA @ lucian @ c:irua:107344 Serial 1304  
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Author Schryvers, D.; Van Aert, S.; Delville, R.; Idrissi, H.; Turner, S.; Salje, E.K.H. pdf  doi
openurl 
  Title Dedicated TEM on domain boundaries from phase transformations and crystal growth Type A1 Journal article
  Year 2013 Publication Phase transitions Abbreviated Journal Phase Transit  
  Volume 86 Issue 1 Pages 15-22  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Investigating domain boundaries and their effects on the behaviour of materials automatically implies the need for detailed knowledge on the structural aspects of the atomic configurations at these interfaces. Not only in view of nearest neighbour interactions but also at a larger scale, often surpassing the unit cell, the boundaries can contain structural elements that do not exist in the bulk. In the present contribution, a number of special boundaries resulting from phase transformations or crystal growth and those recently investigated by advanced transmission electron microscopy techniques in different systems will be reviewed. These include macrotwins between microtwinned martensite plates in NiAl, austenite-single variant martensite habit planes in low hysteresis NiTiPd, nanotwins in non-textured nanostructured Pd and ferroelastic domain boundaries in CaTiO3. In all discussed cases these boundaries play an essential role in the properties of the respective materials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York Editor  
  Language Wos 000312586700003 Publication Date 2012-12-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0141-1594;1029-0338; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.06 Times cited Open Access  
  Notes Fwo; Iap Approved Most recent IF: 1.06; 2013 IF: 1.044  
  Call Number UA @ lucian @ c:irua:101222 Serial 612  
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Author Van Aert, S.; Batenburg, K.J.; Rossell, M.D.; Erni, R.; Van Tendeloo, G. pdf  doi
openurl 
  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 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  
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Author Kundu, P.; Turner, S.; Van Aert, S.; Ravishankar, N.; Van Tendeloo, G. pdf  doi
openurl 
  Title Atomic structure of quantum gold nanowires : quantification of the lattice strain Type A1 Journal article
  Year 2014 Publication ACS nano Abbreviated Journal Acs Nano  
  Volume 8 Issue 1 Pages 599-606  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Theoretical studies exist to compute the atomic arrangement in gold nanowires and the influence on their electronic behavior with decreasing diameter. Experimental studies, e.g., by transmission electron microscopy, on chemically synthesized ultrafine wires are however lacking owing to the unavailability of suitable protocols for sample preparation and the stability of the wires under electron beam irradiation. In this work, we present an atomic scale structural investigation on quantum single crystalline gold nanowires of 2 nm diameter, chemically prepared on a carbon film grid. Using low dose aberration-corrected high resolution (S)TEM, we observe an inhomogeneous strain distribution in the crystal, largely concentrated at the twin boundaries and the surface along with the presence of facets and surface steps leading to a noncircular cross section of the wires. These structural aspects are critical inputs needed to determine their unique electronic character and their potential as a suitable catalyst material. Furthermore, electron-beam-induced structural changes at the atomic scale, having implications on their mechanical behavior and their suitability as interconnects, are discussed.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000330542900061 Publication Date 2013-11-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 13.942 Times cited 20 Open Access  
  Notes FWO; Countatoms; Hercules Approved Most recent IF: 13.942; 2014 IF: 12.881  
  Call Number UA @ lucian @ c:irua:113856 Serial 199  
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Author Ren, P.; Zhang, T.; Jain, N.; Ching, H.Y.V.; Jaworski, A.; Barcaro, G.; Monti, S.; Silvestre-Albero, J.; Celorrio, V.; Chouhan, L.; Rokicinska, A.; Debroye, E.; Kustrowski, P.; Van Doorslaer, S.; Van Aert, S.; Bals, S.; Das, S. pdf  doi
openurl 
  Title An atomically dispersed Mn-photocatalyst for generating hydrogen peroxide from seawater via the Water Oxidation Reaction (WOR) Type A1 Journal article
  Year 2023 Publication Journal of the American Chemical Society Abbreviated Journal  
  Volume 145 Issue 30 Pages 16584-16596  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Organic synthesis (ORSY); Theory and Spectroscopy of Molecules and Materials (TSM²)  
  Abstract In this work, we have fabricatedan aryl amino-substitutedgraphiticcarbon nitride (g-C3N4) catalyst with atomicallydispersed Mn capable of generating hydrogen peroxide (H2O2) directly from seawater. This new catalyst exhibitedexcellent reactivity, obtaining up to 2230 & mu;M H2O2 in 7 h from alkaline water and up to 1800 & mu;Mfrom seawater under identical conditions. More importantly, the catalystwas quickly recovered for subsequent reuse without appreciable lossin performance. Interestingly, unlike the usual two-electron oxygenreduction reaction pathway, the generation of H2O2 was through a less common two-electron water oxidation reaction(WOR) process in which both the direct and indirect WOR processesoccurred; namely, photoinduced h(+) directly oxidized H2O to H2O2 via a one-step 2e(-) WOR, and photoinduced h(+) first oxidized a hydroxide (OH-) ion to generate a hydroxy radical ((OH)-O-& BULL;), and H2O2 was formed indirectly by thecombination of two (OH)-O-& BULL;. We have characterized thematerial, at the catalytic sites, at the atomic level using electronparamagnetic resonance, X-ray absorption near edge structure, extendedX-ray absorption fine structure, high-resolution transmission electronmicroscopy, X-ray photoelectron spectroscopy, magic-angle spinningsolid-state NMR spectroscopy, and multiscale molecular modeling, combiningclassical reactive molecular dynamics simulations and quantum chemistrycalculations.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001034983300001 Publication Date 2023-07-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0002-7863 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 15 Times cited 21 Open Access Not_Open_Access  
  Notes S.D. thanks the IOF grant and Francqui start up grant from the University of Antwerp, Belgium, for the financial support. P.R. thanks CSC and T.Z. thanks FWO for their financial assistance to finish this work. E.D. would like to thank the KU Leuven Research Fund for financial support through STG/21/010. J.S.A. acknowledges financial support from MCIN/AEI/10.13039/501100011033 and EU NextGeneration/PRTR (Project PCI2020-111968/3D-Photocat) and Diamond Synchrotron (rapid access proposal SP32609). This work was supported by the European Research Council (grant 770887-PICOMETRICS to S.V.A. and Grant 815128-REALNANO to S.B.). S.B. and S.V.A. acknowledge financial support from the Research Foundation Flanders (FWO, Belgium, project G.0346.21 N). We also thank Mr. Jian Zhu and Mr. Shahid Ullah Khan from the University of Antwerp, Belgium, for helpful discussions. Approved Most recent IF: 15; 2023 IF: 13.858  
  Call Number UA @ admin @ c:irua:198426 Serial 8831  
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Author Morozov, V.A.; Bertha, A.; Meert, K.W.; Van Rompaey, S.; Batuk, D.; Martinez, G.T.; Van Aert, S.; Smet, P.F.; Raskina, M.V.; Poelman, D.; Abakumov, A.M.; Hadermann, J.; doi  openurl
  Title Incommensurate modulation and luminescence in the CaGd2(1-x)Eu2x(MoO4)4(1-y)(WO)4y (0\leq x\leq1, 0\leq y\leq1) red phosphors Type A1 Journal article
  Year 2013 Publication Chemistry of materials Abbreviated Journal Chem Mater  
  Volume 25 Issue 21 Pages 4387-4395  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Scheelite related compounds (A',A '') [(B',B '')O-4], with B', B '' = W and/or Mo are promising new light-emitting materials for photonic applications, including phosphor converted LEDs (light-emitting diodes). In this paper, the creation and ordering of A-cation vacancies and the effect of cation substitutions in the scheelite-type framework are investigated as a factor for controlling the scheelite-type structure and luminescent properties. CaGd2(1-x)Eu2x(MoO4)(4(1-y))(WO4)(4y) (0 <= x <= 1, 0 <= y <= 1) solid solutions with scheelite-type structure were synthesized by a solid state method, and their structures were investigated using a combination of transmission electron microscopy techniques and powder X-ray diffraction. Within this series all complex molybdenum oxides have (3 + 2)D incommensurately modulated structures with superspace group I4(1)/a(alpha,beta,0)00(-beta,alpha,0)00, while the structures of all tungstates are (3 + 1)D incommensurately modulated with superspace group I2/b(alpha beta 0)00. In both cases the modulation arises because of cation-vacancy ordering at the A site. The prominent structural motif is formed by columns of A-site vacancies running along the c-axis. These vacant columns occur in rows of two or three aligned along the [110] direction of the scheelite subcell. The replacement of the smaller Gd3+ by the larger Eu3+ at the A-sublattice does not affect the nature of the incommensurate modulation, but an increasing replacement of Mo6+ by W6+ switches the modulation from (3 + 2)D to (3 + 1)D regime. Thus, these solid solutions can be considered as a model system where the incommensurate modulation can be monitored as a function of cation nature while the number of cation vacancies at the A sites remain constant upon the isovalent cation replacement. All compounds' luminescent properties were measured, and the optical properties were related to the structural properties of the materials. CaGd2(1-x)(MoO4)(4(1-y))(WO4)(4y) phosphors emit intense red light dominated by the D-5(0)-F-7(2) transition at 612 nm, along with other transitions from the D-5(1) and D-5(0) excited states. The intensity of the 5D0-7F2 transition reaches a maximum at x = 0.5 for y = 0 and 1.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000327045000030 Publication Date 2013-09-24  
  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 63 Open Access  
  Notes Approved Most recent IF: 9.466; 2013 IF: 8.535  
  Call Number UA @ lucian @ c:irua:112776 Serial 1594  
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Author Hugenschmidt, M.; Jannis, D.; Kadu, A.A.; Grünewald, L.; De Marchi, S.; Perez-Juste, J.; Verbeeck, J.; Van Aert, S.; Bals, S. pdf  doi
openurl 
  Title Low-dose 4D-STEM tomography for beam-sensitive nanocomposites Type A1 Journal article
  Year 2023 Publication ACS materials letters Abbreviated Journal  
  Volume 6 Issue 1 Pages 165-173  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Electron tomography is essential for investigating the three-dimensional (3D) structure of nanomaterials. However, many of these materials, such as metal-organic frameworks (MOFs), are extremely sensitive to electron radiation, making it difficult to acquire a series of projection images for electron tomography without inducing electron-beam damage. Another significant challenge is the high contrast in high-angle annular dark field scanning transmission electron microscopy that can be expected for nanocomposites composed of a metal nanoparticle and an MOF. This strong contrast leads to so-called metal artifacts in the 3D reconstruction. To overcome these limitations, we here present low-dose electron tomography based on four-dimensional scanning transmission electron microscopy (4D-STEM) data sets, collected using an ultrafast and highly sensitive direct electron detector. As a proof of concept, we demonstrate the applicability of the method for an Au nanostar embedded in a ZIF-8 MOF, which is of great interest for applications in various fields, including drug delivery.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001141178500001 Publication Date 2023-12-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2639-4979 ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access Not_Open_Access  
  Notes This work was supported by the European Research Council (Grant 815128 REALNANO to S.B., Grant 770887 PICOMETRICS to S.V.A.). J.P.-J. and S.M. acknowledge financial support from the MCIN/AEI/10.13039/501100011033 (Grants No. PID2019-108954RB-I00) and EU Horizon 2020 research and innovation program under grant agreement no. 883390 (SERSing). J.V., S.B., S.V.A., and L.G. acknowledge funding from the Flemish government (iBOF-21-085 PERsist). Approved no  
  Call Number UA @ admin @ c:irua:202771 Serial 9053  
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Author Hao, Y.; Velpula, G.; Kaltenegger, M.; Bodlos, W.R.; Vibert, F.; Mali, K.S.; De Feyter, S.; Resel, R.; Geerts, Y.H.; Van Aert, S.; Beljonne, D.; Lazzaroni, R. pdf  doi
openurl 
  Title From 2D to 3D : bridging self-assembled monolayers to a substrate-induced polymorph in a molecular semiconductor Type A1 Journal article
  Year 2022 Publication Chemistry of materials Abbreviated Journal Chem Mater  
  Volume 34 Issue 5 Pages 2238-2248  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract In this study, a new bottom-up approach is proposed to predict the crystal structure of the substrate-induced polymorph (SIP) of an archetypal molecular semiconductor. In spite of intense efforts, the formation mechanism of SIPs is still not fully understood, and predicting their crystal structure is a very delicate task. Here, we selected lead phthalocyanine (PbPc) as a prototypical molecular material because it is a highly symmetrical yet nonplanar molecule and we demonstrate that the growth and crystal structure of the PbPc SIPs can be templated by the corresponding physisorbed self-assembled molecular networks (SAMNs). Starting from SAMNs of PbPc formed at the solution/graphite interface, the structural and energetic aspects of the assembly were studied by a combination of in situ scanning tunneling microscopy and multiscale computational chemistry approach. Then, the growth of a PbPc SIP on top of the physisorbed monolayer was modeled without prior experimental knowledge, from which the crystal structure of the SIP was predicted. The theoretical prediction of the SIP was verified by determining the crystal structure of PbPc thin films using X-ray diffraction techniques, revealing the formation of a new polymorph of PbPc on the graphite substrate. This study clearly illustrates the correlation between the SAMNs and SIPs, which are traditionally considered as two separate but conceptually connected research areas. This approach is applicable to molecular materials in general to predict the crystal structure of their SIPs.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000812125800001 Publication Date 2022-02-17  
  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 8.6 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 8.6  
  Call Number UA @ admin @ c:irua:189086 Serial 7084  
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Author Jones, L.; Martinez, G.T.; Béché, A.; Van Aert, S.; Nellist, P.D. doi  openurl
  Title Getting the best from an imperfect detector : an alternative normalisation procedure for quantitative HAADF STEM Type A1 Journal article
  Year 2014 Publication Microscopy and microanalysis Abbreviated Journal Microsc Microanal  
  Volume 20 Issue S3 Pages 126-127  
  Keywords A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Cambridge, Mass. Editor  
  Language Wos Publication Date 2014-08-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1431-9276 ISBN Additional Links UA library record  
  Impact Factor 1.891 Times cited Open Access  
  Notes Approved Most recent IF: 1.891; 2014 IF: 1.877  
  Call Number UA @ lucian @ c:irua:136445 Serial 4500  
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Author van den Broek, W.; Van Aert, S.; van Dyck, D. doi  openurl
  Title Fully automated measurement of the modulation transfer function of charge-coupled devices above the Nyquist frequency Type A1 Journal article
  Year 2012 Publication Microscopy and microanalysis Abbreviated Journal Microsc Microanal  
  Volume 18 Issue 2 Pages 336-342  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract The charge-coupled devices used in electron microscopy are coated with a scintillating crystal that gives rise to a severe modulation transfer function (MTF). Exact knowledge of the MTF is imperative for a good correspondence between image simulation and experiment. We present a practical method to measure the MTF above the Nyquist frequency from the beam blocker's shadow image. The image processing has been fully automated and the program is made public. The method is successfully tested on three cameras with various beam blocker shapes.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Cambridge, Mass. Editor  
  Language Wos 000302084700011 Publication Date 2012-02-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1431-9276;1435-8115; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.891 Times cited 15 Open Access  
  Notes Fwo Approved Most recent IF: 1.891; 2012 IF: 2.495  
  Call Number UA @ lucian @ c:irua:96557 Serial 1297  
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Author van Dyck, D.; Van Aert, S.; den Dekker, A.J. doi  openurl
  Title Physical limits on atomic resolution Type A1 Journal article
  Year 2004 Publication Microscopy and microanalysis Abbreviated Journal Microsc Microanal  
  Volume 10 Issue Pages 153-157  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Cambridge, Mass. Editor  
  Language Wos 000188882100022 Publication Date 2004-08-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1431-9276;1435-8115; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.891 Times cited 14 Open Access  
  Notes Approved Most recent IF: 1.891; 2004 IF: 2.389  
  Call Number UA @ lucian @ c:irua:47515 Serial 2616  
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Author Van Aert, S.; den Dekker, A.J.; van den Bos, A.; van Dyck, D. doi  openurl
  Title Statistical experimental design for quantitative atomic resolution transmission electron microscopy Type H1 Book chapter
  Year 2004 Publication Abbreviated Journal Adv Imag Elect Phys  
  Volume Issue Pages 1-164  
  Keywords H1 Book chapter; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Academic Press Place of Publication San Diego, Calif. Editor  
  Language Wos 000223226700001 Publication Date 2011-01-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1076-5670; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 13 Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:47513 Serial 3156  
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Author Van Aert, S.; den Dekker, A.J.; van Dyck, D.; van den Bos, A. doi  openurl
  Title High-resolution electron microscopy and electron tomography: resolution versus precision Type A1 Journal article
  Year 2002 Publication Journal of structural biology Abbreviated Journal J Struct Biol  
  Volume 138 Issue Pages 21-33  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York Editor  
  Language Wos 000177978800003 Publication Date 2002-09-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1047-8477; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.767 Times cited 33 Open Access  
  Notes Approved Most recent IF: 2.767; 2002 IF: 4.194  
  Call Number UA @ lucian @ c:irua:47520 Serial 1446  
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Author van Dyck, D.; Van Aert, S.; den Dekker, A.J.; van den Bos, A. doi  openurl
  Title Is atomic resolution transmission electron microscopy able to resolve and refine amorphous structures? Type A1 Journal article
  Year 2003 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy  
  Volume 98 Issue Pages 27-42  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000186831500003 Publication Date 2003-04-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.843 Times cited 26 Open Access  
  Notes Approved Most recent IF: 2.843; 2003 IF: 1.665  
  Call Number UA @ lucian @ c:irua:47516 Serial 1749  
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Author Van Aert, S.; den Dekker, A.J.; van Dyck, D.; van den Bos, A. doi  openurl
  Title Optimal experimental design of STEM measurement of atom column positions Type A1 Journal article
  Year 2002 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy  
  Volume 90 Issue Pages 273-289  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000174770900004 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.843 Times cited 35 Open Access  
  Notes Approved Most recent IF: 2.843; 2002 IF: 1.772  
  Call Number UA @ lucian @ c:irua:47517 Serial 2483  
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Author den Dekker, A.J.; Van Aert, S.; van Dyck, D.; van den Bos, A.; Geuens, P. doi  openurl
  Title Does a monochromator improve the precision in quantitative HRTEM? Type A1 Journal article
  Year 2001 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy  
  Volume 89 Issue Pages 275-290  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000172667000004 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.843 Times cited 22 Open Access  
  Notes Approved Most recent IF: 2.843; 2001 IF: 1.890  
  Call Number UA @ lucian @ c:irua:47518 Serial 746  
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Author Wang, A.; Chen, F.R.; Van Aert, S.; van Dyck, D. pdf  doi
openurl 
  Title Direct structure inversion from exit waves : part 2 : a practical example Type A1 Journal article
  Year 2012 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy  
  Volume 116 Issue Pages 77-85  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract This paper is the second part of a two-part paper on direct structure inversion from exit waves. In the first part, a method has been proposed to quantitatively determine structure parameters with atomic resolution such as atom column positions, surface profile and the number of atoms in the atom columns. In this part, the theory will be demonstrated by means of a Au[110] exit wave reconstructed from a set of focal-series images. The procedures to analyze the experimentally reconstructed exit wave in terms of quantitative structure information are described in detail.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000304473700011 Publication Date 2012-03-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.843 Times cited 8 Open Access  
  Notes Fwo Approved Most recent IF: 2.843; 2012 IF: 2.470  
  Call Number UA @ lucian @ c:irua:96660 Serial 724  
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Author Wang, A.; Van Aert, S.; Goos, P.; van Dyck, D. pdf  doi
openurl 
  Title Precision of three-dimensional atomic scale measurements from HRTEM images : what are the limits? Type A1 Journal article
  Year 2012 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy  
  Volume 114 Issue Pages 20-30  
  Keywords A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT); Vision lab  
  Abstract In this paper, we investigate to what extent high resolution transmission electron microscopy images can be used to measure the mass, in terms of thickness, and surface profile, corresponding to the defocus offset, of an object at the atomic scale. Therefore, we derive an expression for the statistical precision with which these object parameters can be estimated in a quantitative analysis. Evaluating this expression as a function of the microscope settings allows us to derive the optimal microscope design. Acquiring three-dimensional structure information in terms of thickness turns out to be much more difficult than obtaining two-dimensional information on the projected atom column positions. The attainable precision is found to be more strongly affected by processes influencing the image contrast, such as phonon scattering, than by the specific choice of microscope settings. For a realistic incident electron dose, it is expected that atom columns can be distinguished with single atom sensitivity up to a thickness of the order of the extinction distance. A comparable thickness limit is determined to measure surface steps of one atom. An increase of the electron dose shifts the limiting thickness upward due to an increase in the signal-to-noise ratio.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000301954300003 Publication Date 2012-01-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.843 Times cited 5 Open Access  
  Notes Fwo Approved Most recent IF: 2.843; 2012 IF: 2.470  
  Call Number UA @ lucian @ c:irua:94116 Serial 2692  
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Author Wang, A.; Chen, F.R.; Van Aert, S.; van Dyck, D. pdf  doi
openurl 
  Title A method to determine the local surface profile from reconstructed exit waves Type A1 Journal article
  Year 2011 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy  
  Volume 111 Issue 8 Pages 1352-1359  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract Reconstructed exit waves are useful to quantify unknown structure parameters such as the position and composition of the atom columns at atomic scale. Existing techniques provide a complex wave in a flat plane which is close to the plane where the electrons leave the atom columns. However, due to local deviation in the flatness of the exit surface, there will be an offset between the plane of reconstruction and the actual exit of a specific atom column. Using the channelling theory, it has been shown that this defocus offset can in principle be determined atom column-by-atom column. As such, the surface roughness could be quantified at atomic scale. However, the outcome strongly depends on the initial plane of reconstruction especially in a crystalline structure. If this plane is further away from the true exit, the waves of the atom columns become delocalized and interfere mutually which strongly complicates the interpretation of the exit wave in terms of the local structure. In this paper, we will study the delocalization with defocus using the channelling theory in a more systematic way.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000300461100049 Publication Date 2011-05-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.843 Times cited 3 Open Access  
  Notes Fwo Approved Most recent IF: 2.843; 2011 IF: 2.471  
  Call Number UA @ lucian @ c:irua:88941 Serial 2017  
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Author van den Broek, W.; Van Aert, S.; Goos, P.; van Dyck, D. pdf  doi
openurl 
  Title Throughput maximization of particle radius measurements by balancing size and current of the electron probe Type A1 Journal article
  Year 2011 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy  
  Volume 111 Issue 7 Pages 940-947  
  Keywords A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT); Vision lab  
  Abstract In thispaperweinvestigatewhichprobesizemaximizesthethroughputwhenmeasuringtheradiusof nanoparticlesinhighangleannulardarkfieldscanningtransmissionelectronmicroscopy(HAADFSTEM). The sizeandthecorrespondingcurrentoftheelectronprobedeterminetheprecisionoftheestimateofa particlesradius.Maximizingthroughputmeansthatamaximumnumberofparticlesshouldbeimaged withinagiventimeframe,sothataprespecifiedprecisionisattained.WeshowthatBayesianstatistical experimentaldesignisaveryusefulapproachtodeterminetheoptimalprobesizeusingacertainamount of priorknowledgeaboutthesample.Thedependenceoftheoptimalprobesizeonthedetectorgeometry and thediameter,variabilityandatomicnumberoftheparticlesisinvestigated.Anexpressionforthe optimalprobesizeintheabsenceofanykindofpriorknowledgeaboutthespecimenisderivedaswell.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000300461000026 Publication Date 2010-11-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.843 Times cited 7 Open Access  
  Notes Approved Most recent IF: 2.843; 2011 IF: 2.471  
  Call Number UA @ lucian @ c:irua:89657 Serial 3659  
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Author Van Aert, S.; Chen, J.H.; van Dyck, D. pdf  doi
openurl 
  Title Linear versus non-linear structural information limit in high-resolution transmission electron microscopy Type A1 Journal article
  Year 2010 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy  
  Volume 110 Issue 11 Pages 1404-1410  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract A widely used performance criterion in high-resolution transmission electron microscopy (HRTEM) is the information limit. It corresponds to the inverse of the maximum spatial object frequency that is linearly transmitted with sufficient intensity from the exit plane of the object to the image plane and is limited due to partial temporal coherence. In practice, the information limit is often measured from a diffractogram or from Young's fringes assuming a weak phase object scattering beyond the inverse of the information limit. However, for an aberration corrected electron microscope, with an information limit in the sub-angstrom range, weak phase objects are no longer applicable since they do not scatter sufficiently in this range. Therefore, one relies on more strongly scattering objects such as crystals of heavy atoms observed along a low index zone axis. In that case, dynamical scattering becomes important such that the non-linear and linear interaction may be equally important. The non-linear interaction may then set the experimental cut-off frequency observed in a diffractogram. The goal of this paper is to quantify both the linear and the non-linear information transfer in terms of closed form analytical expressions. Whereas the cut-off frequency set by the linear transfer can be directly related with the attainable resolution, information from the non-linear transfer can only be extracted using quantitative, model-based methods. In contrast to the historic definition of the information limit depending on microscope parameters only, the expressions derived in this paper explicitly incorporate their dependence on the structure parameters as well. In order to emphasize this dependence and to distinguish from the usual information limit, the expressions derived for the inverse cut-off frequencies will be referred to as the linear and non-linear structural information limit. The present findings confirm the well-known result that partial temporal coherence has different effects on the transfer of the linear and non-linear terms, such that the non-linear imaging contributions are damped less than the linear imaging contributions at high spatial frequencies. This will be important when coherent aberrations such as spherical aberration and defocus are reduced.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000282562100008 Publication Date 2010-07-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.843 Times cited 6 Open Access  
  Notes Fwo Approved Most recent IF: 2.843; 2010 IF: 2.063  
  Call Number UA @ lucian @ c:irua:83689 Serial 1821  
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Author Wang, A.; Chen, F.R.; Van Aert, S.; van Dyck, D. pdf  doi
openurl 
  Title Direct structure inversion from exit waves: part 1: theory and simulations Type A1 Journal article
  Year 2010 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy  
  Volume 110 Issue 5 Pages 527-534  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract In order to interpret the amplitude and phase of the exit wave in terms of mass and position of the atoms, one has to invert the dynamic scattering of the electrons in the object so as to obtain a starting structure which can then be used as a seed for further quantitative structure refinement. This is especially challenging in case of a zone axis condition when the interaction of the electrons with the atom column is very strong. Based on the channelling theory we will show that the channelling map not only yields a circle on the Argand plot but also a circular defocus curve for every column. The former gives the number of atoms in each column, while the latter provides the defocus value for each column, which reveals the surface roughness at the exit plane with single atom sensitivity.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000279065700019 Publication Date 2009-12-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.843 Times cited 25 Open Access  
  Notes Fwo Approved Most recent IF: 2.843; 2010 IF: 2.063  
  Call Number UA @ lucian @ c:irua:83691 Serial 723  
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