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Author Amini, M.N.; Altantzis, T.; Lobato, I.; Grzelczak, M.; Sánchez-Iglesias, A.; Van Aert, S.; Liz-Marzán, L.M.; Partoens, B.; Bals, S.; Neyts, E.C.
Title Understanding the Effect of Iodide Ions on the Morphology of Gold Nanorods Type A1 Journal article
Year (down) 2018 Publication Particle and particle systems characterization Abbreviated Journal Part Part Syst Char
Volume 35 Issue 35 Pages 1800051
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The presence of iodide ions during the growth of gold nanorods strongly affects the shape of the final products, which is proposed to be due to selective iodide adsorption on certain crystallographic facets. Therefore, a detailed structural and morphological characterization of the starting rods is crucial toward understanding this effect. Electron tomography is used to determine the crystallographic indices of the lateral facets of gold nanorods, as well as those present at the tips. Based on this information, density functional theory calculations are used to determine the surface and interface energies of the observed facets and provide insight into the relationship between the amount of iodide ions in the growth solution and the final morphology of anisotropic gold nanoparticles.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000441893400002 Publication Date 2018-06-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0934-0866 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.474 Times cited 6 Open Access OpenAccess
Notes This work was supported by the European Research Council (grant 335078 COLOURATOM to S.B.). T.A., S.V.A. S.B. and E.C.N., acknowledge funding from the Research Foundation Flanders (FWO, Belgium), through project funding (G.0218.14N and G.0369.15N) and a postdoctoral grant to T.A. L.M.L.-M. and M.G. acknowledge funding from the Spanish Ministerio de Economía y Competitividad (grant MAT2013-46101-R). Mozhgan N. Amini and Thomas Altantzis contributed equally to this work. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); ecas_sara Approved Most recent IF: 4.474
Call Number EMAT @ emat @c:irua:152998UA @ admin @ c:irua:152998 Serial 5010
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Author Hu, L.; Amini, M.N.; Wu, Y.; Jin, Z.; Yuan, J.; Lin, R.; Wu, J.; Dai, Y.; He, H.; Lu, Y.; Lu, J.; Ye, Z.; Han, S.-T.; Ye, J.; Partoens, B.; Zeng, Y.-J.; Ruan, S.
Title Charge transfer doping modulated raman scattering and enhanced stability of black phosphorus quantum dots on a ZnO nanorod Type A1 Journal article
Year (down) 2018 Publication Advanced Optical Materials Abbreviated Journal Adv Opt Mater
Volume 6 Issue 15 Pages 1800440
Keywords A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Black phosphorus (BP) has recently triggered an unprecedented interest in the 2D community. However, many of its unique properties are not exploited and the well-known environmental vulnerability is not conquered. Herein, a type-I mixed-dimensional (0D-1D) van der Waals heterojunction is developed, where three-atomic-layer BP quantum dots (QDs) are assembled on a single ZnO nanorod (NR). By adjusting the indium (In) content in ZnO NRs, the degree and even the direction of surface charge transfer doping within the heterojunction can be tuned, which result in selective Raman scattering enhancements between ZnO and BP. The maximal enhancement factor is determined as 4340 for BP QDs with sub-ppm level. Furthermore, an unexpected long-term ambient stability (more than six months) of BP QDs is revealed, which is ascribed to the electron doping from ZnO:In NRs. The first demonstration of selective Raman enhancements between two inorganic semiconductors as well as the improved stability of BP shed light on this emerging 2D material.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000440815200023 Publication Date 2018-05-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2195-1071 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.875 Times cited 37 Open Access Not_Open_Access
Notes ; L. Hu and M. N. Amini contributed equally to this work. This work was supported by the National Natural Science Foundation of China under Grant Nos. 51502178, 81571763 and 81622026, the Shenzhen Science and Technology Project under Grant Nos. JCYJ20150324141711644, JCYJ20170412105400428, KQJSCX20170727101208249 and JCYJ20170302153853962. Parts of the computational calculations were carried out using the HPC infrastructure at University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, supported financially by the FWO-Vlaanderen and the Flemish Government (EWI Department). L. H. acknowledges the PhD Start-up Fund of Natural Science Foundation of Guangdong Province under Grand No. 2017A030310072. J. Y. acknowledges the funding of Shanghai Jiao Tong University (Nos. YG2016MS51 and YG2017MS54). ; Approved Most recent IF: 6.875
Call Number UA @ lucian @ c:irua:153112UA @ admin @ c:irua:153112 Serial 5082
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Author Momot, A.; Amini, M.N.; Reekmans, G.; Lamoen, D.; Partoens, B.; Slocombe, D.R.; Elen, K.; Adriaensens, P.; Hardy, A.; Van Bael, M.K.
Title A novel explanation for the increased conductivity in annealed Al-doped ZnO: an insight into migration of aluminum and displacement of zinc Type A1 Journal article
Year (down) 2017 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 19 Issue 40 Pages 27866-27877
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract A combined experimental and first-principles study is performed to study the origin of conductivity in

ZnO:Al nanoparticles synthesized under controlled conditions via a reflux route using benzylamine as a

solvent. The experimental characterization of the samples by Raman, nuclear magnetic resonance (NMR)

and conductivity measurements indicates that upon annealing in nitrogen, the Al atoms at interstitial

positions migrate to the substitutional positions, creating at the same time Zn interstitials. We provide

evidence for the fact that the formed complex of AlZn and Zni corresponds to the origin of the Knight

shifted peak (KS) we observe in 27Al NMR. As far as we know, the role of this complex has not been

discussed in the literature to date. However, our first-principles calculations show that such a complex is

indeed energetically favoured over the isolated Al interstitial positions. In our calculations we also

address the charge state of the Al interstitials. Further, Zn interstitials can migrate from Al_Zn and possibly

also form Zn clusters, leading to the observed increased conductivity.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000413290500073 Publication Date 2017-10-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.123 Times cited 26 Open Access OpenAccess
Notes We want to thank the Interuniversity Attraction Poles Programme (P7/05) initiated by the Belgian Science Policy Office (BELSPO) for the financial support. We also acknowledge the Research Foundation Flanders (FWO-Vlaanderen) for support via the MULTIMAR WOG project and under project No. G018914. The computational parts were carried out using the HPC infrastructure at the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, supported financially by the Hercules foundation and the Flemish Government (EWI Department). Approved Most recent IF: 4.123
Call Number EMAT @ emat @c:irua:146878 Serial 4760
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Author Zeng, Y.-J.; Schouteden, K.; Amini, M.N.; Ruan, S.-C.; Lu, Y.-F.; Ye, Z.-Z.; Partoens, B.; Lamoen, D.; Van Haesendonck, C.
Title Electronic band structures and native point defects of ultrafine ZnO nanocrystals Type A1 Journal article
Year (down) 2015 Publication ACS applied materials and interfaces Abbreviated Journal Acs Appl Mater Inter
Volume 7 Issue 7 Pages 10617-10622
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract Ultrafine ZnO nanocrystals with a thickness down to 0.25 nm are grown by a metalorganic chemical vapor deposition method. Electronic band structures and native point defects of ZnO nanocrystals are studied by a combination of scanning tunneling microscopy/spectroscopy and first-principles density functional theory calculations. Below a critical thickness of nm ZnO adopts a graphitic-like structure and exhibits a wide band gap similar to its wurtzite counterpart. The hexagonal wurtzite structure, with a well-developed band gap evident from scanning tunneling spectroscopy, is established for a thickness starting from similar to 1.4 nm. With further increase of the thickness to 2 nm, V-O-V-Zn defect pairs are easily produced in ZnO nanocrystals due to the self-compensation effect in highly doped semiconductors.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000355055000063 Publication Date 2015-04-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1944-8244;1944-8252; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.504 Times cited 15 Open Access
Notes Hercules; EWI Approved Most recent IF: 7.504; 2015 IF: 6.723
Call Number c:irua:126408 Serial 999
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Author Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B.
Title The role of the VZn-NO-H complex in the p-type conductivity in ZnO Type A1 Journal article
Year (down) 2015 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 17 Issue 17 Pages 5485-5489
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract Past research efforts aiming at obtaining stable p-type ZnO have been based on complexes involving nitrogen doping. A recent experiment by (J. G. Reynolds et al., Appl. Phys. Lett., 2013, 102, 152114) demonstrated a significant ([similar]1018 cm−3) p-type behavior in N-doped ZnO films after appropriate annealing. The p-type conductivity was attributed to a VZnNOH shallow acceptor complex, formed by a Zn vacancy (VZn), N substituting O (NO), and H interstitial (Hi). We present here a first-principles hybrid functional study of this complex compared to the one without hydrogen. Our results confirm that the VZnNOH complex acts as an acceptor in ZnO. We find that H plays an important role, because it lowers the formation energy of the complex with respect to VZnNO, a complex known to exhibit (unstable) p-type behavior. However, this additional H atom also occupies the hole level at the origin of the shallow behavior of VZnNO, leaving only two states empty higher in the band gap and making the VZnNOH complex a deep acceptor. Therefore, we conclude that the cause of the observed p-type conductivity in experiment is not the presence of the VZnNOH complex, but probably the formation of the VZnNO complex during the annealing process.
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Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000349616400080 Publication Date 2015-01-20
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 20 Open Access
Notes FWO G021614N; FWO G015013; FWO G018914N; GOA; Hercules Approved Most recent IF: 4.123; 2015 IF: 4.493
Call Number c:irua:123218 Serial 3592
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Author Amini, M.N.; Dixit, H.; Saniz, R.; Lamoen, D.; Partoens, B.
Title The origin of p-type conductivity in ZnM2O4 (M = Co, Rh, Ir) spinels Type A1 Journal article
Year (down) 2014 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 16 Issue 6 Pages 2588-2596
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract ZnM2O4 (M = Co, Rh, Ir) spinels are considered as a class of potential p-type transparent conducting oxides (TCOs). We report the formation energy of acceptor-like defects using first principles calculations with an advanced hybrid exchange-correlation functional (HSE06) within density functional theory (DFT). Due to the discrepancies between the theoretically obtained band gaps with this hybrid functional and the – scattered – experimental results, we also perform GW calculations to support the validity of the description of these spinels with the HSE06 functional. The considered defects are the cation vacancy and antisite defects, which are supposed to be the leading source of disorder in the spinel structures. We also discuss the band alignments in these spinels. The calculated formation energies indicate that the antisite defects ZnM (Zn replacing M, M = Co, Rh, Ir) and VZn act as shallow acceptors in ZnCo2O4, ZnRh2O4 and ZnIr2O4, which explains the experimentally observed p-type conductivity in those systems. Moreover, our systematic study indicates that the ZnIr antisite defect has the lowest formation energy in the group and it corroborates the highest p-type conductivity reported for ZnIr2O4 among the group of ZnM2O4 spinels. To gain further insight into factors affecting the p-type conductivity, we have also investigated the formation of localized small polarons by calculating the self-trapping energy of the holes.
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Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000329926700040 Publication Date 2013-12-03
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 47 Open Access
Notes Fwo; Goa; Hercules Approved Most recent IF: 4.123; 2014 IF: 4.493
Call Number UA @ lucian @ c:irua:114829 Serial 2525
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Author Dabaghmanesh, S.; Saniz, R.; Amini, M.N.; Lamoen, D.; Partoens, B.
Title Perovskite transparent conducting oxides : an ab initio study Type A1 Journal article
Year (down) 2013 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 25 Issue 41 Pages 415503
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We present an ab initio study of the electronic structure and of the formation energies of various point defects in BaSnO3 and SrGeO3. We show that La and Y impurities substituting Ba or Sr are shallow donors with a preferred 1 + charge state. These defects have a low formation energy within all the suitable equilibrium growth conditions considered. Oxygen vacancies behave as shallow donors as well, preferring the 2 + charge state. Their formation energies, however, are higher in most growth conditions, indicating a limited contribution to conductivity. The calculated electron effective mass in BaSnO3, with a value of 0.21 me, and the very high mobility reported recently in La-doped BaSnO3 single-crystals, suggest that remarkably low scattering rates can be achieved in the latter. In the case of SrGeO3, our results point to carrier density and mobility values in the low range for typical polycrystalline TCOs, in line with experiment.
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Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000324920400011 Publication Date 2013-09-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 17 Open Access
Notes FWO;Hercules Approved Most recent IF: 2.649; 2013 IF: 2.223
Call Number UA @ lucian @ c:irua:110495 Serial 2574
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Author Amini, M.N.; Leenaerts, O.; Partoens, B.; Lamoen, D.
Title Graphane- and fluorographene-based quantum dots Type A1 Journal article
Year (down) 2013 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 117 Issue 31 Pages 16242-16247
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract With the help of first-principles calculations, we investigate graphane/fluorographene heterostructures with special attention for graphane and fluorographene-based quantum dots. Graphane and fluorographene have large electronic band gaps, and we show that their band structures exhibit a strong type-II alignment. In this way, it is possible to obtain confined electron states in fluorographene nanostructures by embedding them in a graphane crystal. Bound hole states can be created in graphane domains embedded in a fluorographene environment. For circular graphane/fluorographene quantum dots, localized states can be observed in the band gap if the size of the radii is larger than approximately 4 to 5 Å.
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Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000323082300046 Publication Date 2013-07-15
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 14 Open Access
Notes FWO; GOW; Hercules Approved Most recent IF: 4.536; 2013 IF: 4.835
Call Number UA @ lucian @ c:irua:109457 Serial 1367
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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 (down) 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.
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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 UA @ lucian @ c:irua:101782 Serial 3004
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Author Matsubara, M.; Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B.
Title Attracting shallow donors : hydrogen passivation in (Al,Ga,In)-doped ZnO Type A1 Journal article
Year (down) 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 86 Issue 16 Pages 165207
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract The hydrogen interstitial and the substitutional AlZn, GaZn, and InZn are all shallow donors in ZnO and lead to n-type conductivity. Although shallow donors are expected to repel each other, we show by first-principles calculations that in ZnO these shallow donor impurities attract and form a complex, leading to a donor level deep in the band gap. This puts a limit on the n-type conductivity of (Al,Ga,In)-doped ZnO in the presence of hydrogen.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000310131300008 Publication Date 2012-10-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 7 Open Access
Notes Iwt; Fwo; Bof-Noi Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:101780 Serial 202
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Author Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B.
Title Hydrogen impurities and native defects in CdO Type A1 Journal article
Year (down) 2011 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 110 Issue 6 Pages 063521,1-063521,7
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract We have used first-principles calculations based on density functional theory to study point defects in CdO within the local density approximation and beyond (LDA+U). Hydrogen interstitials and oxygen vacancies are found to act as shallow donors and can be interpreted as the cause of conductivity in CdO. Hydrogen can also occupy an oxygen vacancy in its substitutional form and also acts as a shallow donor. Similar to what was found for ZnO and MgO, hydrogen creates a multicenter bond with its six oxygen neighbors in CdO. The charge neutrality level for native defects and hydrogen impurities has been calculated. It is shown that in the case of native defects, it is not uniquely defined. Indeed, this level depends highly on the chemical potentials of the species and one can obtain different values for different end states in the experiment. Therefore, a comparison with experiment can only be made if the chemical potentials of the species in the experiment are well defined. However, for the hydrogen interstitial defect, since this level is independent of the chemical potential of hydrogen, one can obtain a unique value for the charge neutrality level. We find that the Fermi level stabilizes at 0.43 eV above the conduction band minimum in the case of the hydrogen interstitial defect, which is in good agreement with the experimentally reported value of 0.4 eV.
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Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000295619300041 Publication Date 2011-09-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.068 Times cited 13 Open Access
Notes ; The authors gratefully acknowledge financial support from the IWT-Vlaanderen through the ISIMADE project, the FWO-Vlaanderen through Project G.0191.08 and the BOF-NOI of the University of Antwerp. This work was carried out using the HPC infrastructure at the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC. ; Approved Most recent IF: 2.068; 2011 IF: 2.168
Call Number UA @ lucian @ c:irua:93613 Serial 1533
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