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“Ab initio study of the X2\Sigma+ and A 2\Pi states of the SiN radical”. Cai ZL, Martin JML, François JP, Gijbels R, Chemical physics letters 252, 398 (1996). http://doi.org/10.1016/0009-2614(96)00183-2
Abstract: The equilibrium bond length, harmonic frequency, first and second order anharmonicity constants, rotational and centrifugal distortion constants, as well as the rotation-vibrational and centrifugal coupling constants for the ground X(2) Sigma(+) and first excited A(2) Pi states of the SiN radical have been calculated at the complete active space SCF (CASSCF), multireference CI (MRCI) and coupled cluster (CCSD(T)) levels using Dunning's correlation-consistent basis sets. The excitation energy of the A(2) Pi State has also been computed at these theoretical levels. Dipole moments of SiN in the X(2) Sigma(+) and A(2) Pi states are given. Our study shows that core correlation must be considered in order to obtain satisfactory accuracy for the spectroscopic constants.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 1.897
Times cited: 28
DOI: 10.1016/0009-2614(96)00183-2
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“Ab initio study of the structure, infrared spectra and heat of formation of C4”. Martin JML, François JP, Gijbels R, The journal of chemical physics 94, 3753 (1991)
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 2.952
Times cited: 62
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“Ab initio study of the spectroscopy, kinetics, and thermochemistry of the C2N and CN2 molecules”. Martin JML, Taylor PR, François JP, Gijbels R, Chemical physics letters 226, 475 (1994). http://doi.org/10.1016/0009-2614(94)00758-6
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.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 1.897
Times cited: 46
DOI: 10.1016/0009-2614(94)00758-6
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“Ab initio study of the spectroscopy, kinetics, and thermochemistry of the BN2 molecule”. Martin JML, Taylor PR, François JP, Gijbels R, Chemical physics letters 222, 517 (1994). http://doi.org/10.1016/0009-2614(94)00378-5
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 1.897
Times cited: 14
DOI: 10.1016/0009-2614(94)00378-5
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“Ab initio study of the adsorption of O, O2, H2O and H2O2 on UO2 surfaces using DFT+U and non-collinear magnetism”. Arts I, Saniz R, Baldinozzi G, Leinders G, Verwerft M, Lamoen D, Journal of Nuclear Materials 599, 155249 (2024). http://doi.org/10.1016/j.jnucmat.2024.155249
Abstract: In order to model correctly the corrosion of spent nuclear fuel under disposal conditions, it is important to understand its behavior in the presence of oxidants. To advance in this direction, we consider the oxidation of UO2. We investigate computationally the adsorption of various species on its three most stable surfaces: (111), (110), and (100), with emphasis on incorporating a full non-collinear PBE+U approach. Various species, namely O, O2, H2O and H2O2 are considered due to their relevance for the oxidation of UO2. The dissociation energy and an estimate for the dissociation barrier for O2 were obtained, using the preferred adsorption configurations of O and O2. The adsorption configurations for H2O in our study compare well with previous studies that used collinear approximations, both in terms of relative stability of configurations and bond lengths. Differences in adsorption energies were found, which may be important for reaction kinetics. Dissociative reactions in which the water molecule splits in hydrogen and hydroxyl occur only on one of the three surfaces. The hydrogen further reacts with a surface oxygen to also form a hydroxyl group. Not surprisingly, we find that H2O2 binds more strongly to the three surfaces than water (lower formation energy), and similar to H2O adsorption, dissociative reactions may occur. The dissociated hydrogen reacts with a surface oxygen to form a hydroxyl group and the hydroperoxyl molecule binds with a surface uranium. Our study, which includes a detailed study of electron transfer, magnetic structure and the preferred adsorption configurations, gives insight into the uranium oxidation states and the influence of surface geometry on adsorption. The findings contribute to a more comprehensive understanding of the early stages of UO2 oxidation.
Keywords: A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
Impact Factor: 3.1
DOI: 10.1016/j.jnucmat.2024.155249
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“Ab initio study of shallow acceptors in bixbyite V2O3”. Sarmadian N, Saniz R, Partoens B, Lamoen D, Journal of applied physics 117, 015703 (2015). http://doi.org/10.1063/1.4905316
Abstract: We present the results of our study on p-type dopability of bixbyite V2O3 using the Heyd, Scuseria, and Ernzerhof hybrid functional (HSE06) within the density functional theory (DFT) formalism. We study vanadium and oxygen vacancies as intrinsic defects and substitutional Mg, Sc, and Y as extrinsic defects. We find that Mg substituting V acts as a shallow acceptor, and that oxygen vacancies are electrically neutral. Hence, we predict Mg-doped V2O3 to be a p-type conductor. Our results also show that vanadium vacancies are relatively shallow, with a binding energy of 0.14 eV, so that they might also lead to p-type conductivity.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Impact Factor: 2.068
Times cited: 3
DOI: 10.1063/1.4905316
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“Ab initio study of hydrogenic effective mass impurities in Si nanowires”. Peelaers H, Durgun E, Partoens B, Bilc DI, Ghosez P, Van de Walle CG, Peeters FM, Journal of physics : condensed matter 29, 095303 (2017). http://doi.org/10.1088/1361-648X/AA5768
Abstract: The effect of B and P dopants on the band structure of Si nanowires is studied using electronic structure calculations based on density functional theory. At low concentrations a dispersionless band is formed, clearly distinguishable from the valence and conduction bands. Although this band is evidently induced by the dopant impurity, it turns out to have purely Si character. These results can be rigorously analyzed in the framework of effective mass theory. In the process we resolve some common misconceptions about the physics of hydrogenic shallow impurities, which can be more clearly elucidated in the case of nanowires than would be possible for bulk Si. We also show the importance of correctly describing the effect of dielectric confinement, which is not included in traditional electronic structure calculations, by comparing the obtained results with those of G(0)W(0) calculations.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.649
Times cited: 1
DOI: 10.1088/1361-648X/AA5768
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“Ab initio spectroscopy and thermochemistry of the BN molecule”. Martin JML, François JP, Gijbels R, Zeitschrift für Physik : D : atoms, molecules and clusters 21, 47 (1991)
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Times cited: 17
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“Ab initio prediction of semiconductivity in a novel two-dimensional Sb₂X₃, (X= S, Se, Te) monolayers with orthorhombic structure”. Bafekry A, Mortazavi B, Faraji M, Shahrokhi M, Shafique A, Jappor HR, Nguyen C, Ghergherehchi M, Feghhi SAH, Scientific Reports 11, 10366 (2021). http://doi.org/10.1038/S41598-021-89944-4
Abstract: Sb2S3 and Sb2Se3 are well-known layered bulk structures with weak van der Waals interactions. In this work we explore the atomic lattice, dynamical stability, electronic and optical properties of Sb2S3, Sb2Se3 and Sb2Te3 monolayers using the density functional theory simulations. Molecular dynamics and phonon dispersion results show the desirable thermal and dynamical stability of studied nanosheets. On the basis of HSE06 and PBE/GGA functionals, we show that all the considered novel monolayers are semiconductors. Using the HSE06 functional the electronic bandgap of Sb2S3, Sb2Se3 and Sb2Te3 monolayers are predicted to be 2.15, 1.35 and 1.37 eV, respectively. Optical simulations show that the first absorption coefficient peak for Sb2S3, Sb2Se3 and Sb2Te3 monolayers along in-plane polarization is suitable for the absorption of the visible and IR range of light. Interestingly, optically anisotropic character along planar directions can be desirable for polarization-sensitive photodetectors. Furthermore, we systematically investigate the electrical transport properties with combined first-principles and Boltzmann transport theory calculations. At optimal doping concentration, we found the considerable larger power factor values of 2.69, 4.91, and 5.45 for hole-doped Sb2S3, Sb2Se3, and Sb2Te3, respectively. This study highlights the bright prospect for the application of Sb2S3, Sb2Se3 and Sb2Te3 nanosheets in novel electronic, optical and energy conversion systems.
Keywords: A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Impact Factor: 4.259
DOI: 10.1038/S41598-021-89944-4
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“Ab initio modeling of few-layer dilute magnetic semiconductors”. Tiwari S, Van de Put ML, Sorée B, Vandenberghe WG, International Conference on Simulation of Semiconductor Processes and Devices : [proceedings]
T2 –, International Conference on Simulation of Semiconductor Processes and, Devices (SISPAD), SEP 27-29, 2021, Dallas, TX , 141 (2021). http://doi.org/10.1109/SISPAD54002.2021.9592535
Abstract: We present a computational model to model the magnetic structure of two-dimensional (2D) dilute-magnetic-semiconductors (DMS) both the monolayers and multilayers using first-principles density functional theory (DFT), as well as their magnetic phase transition as a function of temperature using Monte-Carlo simulations. Using our method, we model the magnetic structure of bulk, bilayer, and monolayer MoS2 substitutionally doped with Fe atoms. We find that the out-of-plane interaction in bilayer MoS2 is weakly ferromagnetic, whereas in bulk MoS2 it is strongly anti-ferromagnetic. Finally, we show that the magnetic order is more robust in bilayer Fe-doped MoS2 compared to the monolayer and results in a room-temperature FM at an atomic substitution of 14-16%.
Keywords: P1 Proceeding; Engineering sciences. Technology; Condensed Matter Theory (CMT)
DOI: 10.1109/SISPAD54002.2021.9592535
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“Ab initio methodology for magnetic exchange parameters: Generic four-state energy mapping onto a Heisenberg spin Hamiltonian”. Sabani D, Bacaksiz C, Milošević, MV, Physical Review B 102, 014457 (2020). http://doi.org/10.1103/PHYSREVB.102.014457
Abstract: The recent development in the field of two-dimensional magnetic materials urges reliable theoretical methodology for determination of magnetic properties. Among the available methods, ab initio four-state energy mapping based on density functional theory stands out as a powerful technique to calculate the magnetic exchange interaction in the Heisenberg spin model. Although the required formulas were explained in earlier works, the considered Hamiltonian in those studies always corresponded to the specific case that the off-diagonal part of J matrix is antisymmetric, which may be misleading in other cases. Therefore, using the most general form of the Heisenberg spin Hamiltonian, we here derive the generic formulas. With a proper choice of four different magnetic states, a single formula governs all elements of the exchange interaction matrix for any considered pair of spin sites.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.7
Times cited: 13
DOI: 10.1103/PHYSREVB.102.014457
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Bekaert J (2018) Ab initio description of multicomponent superconductivity in bulk to atomically thin materials. Antwerpen
Keywords: Doctoral thesis; Condensed Matter Theory (CMT)
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Bekaert J (2018) Ab initio description of multicomponent superconductivity in bulk to atomically thin materials. 290 p
Keywords: Doctoral thesis; Condensed Matter Theory (CMT)
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“ab initio description of bonding for transmission electron microscopy”. Madsen J, Pennycook TJ, Susi T, Ultramicroscopy 231 (2021). http://doi.org/10.1016/J.ULTRAMIC.2021.113253
Abstract: The simulation of transmission electron microscopy (TEM) images or diffraction patterns is often required to interpret their contrast and extract specimen features. This is especially true for high-resolution phase-contrast imaging of materials, but electron scattering simulations based on atomistic models are widely used in materials science and structural biology. Since electron scattering is dominated by the nuclear cores, the scattering potential is typically described by the widely applied independent atom model. This approximation is fast and fairly accurate, especially for scanning TEM (STEM) annular dark-field contrast, but it completely neglects valence bonding and its effect on the transmitting electrons. However, an emerging trend in electron microscopy is to use new instrumentation and methods to extract the maximum amount of information from each electron. This is evident in the increasing popularity of techniques such as 4D-STEM combined with ptychography in materials science, and cryogenic microcrystal electron diffraction in structural biology, where subtle differences in the scattering potential may be both measurable and contain additional insights. Thus, there is increasing interest in electron scattering simulations based on electrostatic potentials obtained from first principles, mainly via density functional theory, which was previously mainly required for holography. In this Review, we discuss the motivation and basis for these developments, survey the pioneering work that has been published thus far, and give our outlook for the future. We argue that a physically better justified ab initio description of the scattering potential is both useful and viable for an increasing number of systems, and we expect such simulations to steadily gain in popularity and importance.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.843
DOI: 10.1016/J.ULTRAMIC.2021.113253
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“Ab initio computation of the mean inner Coulomb potential of wurtzite-type semiconductors and gold”. Schowalter M, Rosenauer A, Lamoen D, Kruse P, Gerthsen D, Applied Physics Letters 88, Artn 232108 (2006). http://doi.org/10.1063/1.2210453
Keywords: A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Impact Factor: 3.411
Times cited: 8
DOI: 10.1063/1.2210453
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“Ab initio computation of the mean inner Coulomb potential of technological important semiconductors”. Schowalter M, Rosenauer A, Lamoen D, Kruse P, Gerthsen D, 1007, 233 (2005)
Keywords: A1 Journal article; Electron Microscopy for Materials Science (EMAT);
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“Ab initio computation of the mean inner Coulomb potential of amorphous carbon structures”. Schowalter M, Titantah JT, Lamoen D, Kruse P, Applied physics letters 86, 112102 (2005). http://doi.org/10.1063/1.1885171
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.411
Times cited: 15
DOI: 10.1063/1.1885171
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“Ab initio calculations and a scratch test study of RF-magnetron sputter deposited hydroxyapatite and silicon-containing hydroxyapatite coatings”. Surmenev RA, Grubova IY, Neyts E, Teresov AD, Koval NN, Epple M, Tyurin AI, Pichugin VF, Chaikina MV, Surmeneva MA, Surfaces and interfaces 21 (2020). http://doi.org/10.1016/J.SURFIN.2020.100727
Abstract: A crucial property for implants is their biocompatibility. To ensure biocompatibility, thin coatings of hydroxyapatite (HA) are deposited on the actual implant. In this study, we investigate the effects of the addition of silicate anions to the structure of hydroxyapatite coatings on their adhesion strength via a scratch test and ab initio calculations. We find that both the grain size and adhesion strength decrease with the increase in the silicon content in the HA coating (SiHA). The increase in the silicon content to 1.2 % in the HA coating leads to a decrease in the average crystallite size from 28 to 21 nm, and in the case of 4.6 %, it leads to the formation of an amorphous or nanocrystalline film. The decreases in the grain and crystallite sizes lead to peeling and destruction of the coating from the titanium substrate at lower loads. Further, our ab initio simulations demonstrate an increased number of molecular bonds at the amorphous SiHA-TiO2 interface. However, the experimental results revealed that the structure and grain size have more pronounced effects on the adhesion strength of the coatings. In conclusion, based on the results of the ab initio simulations and the experimental results, we suggest that the presence of Si in the form of silicate ions in the HA coating has a significant impact on the structure, grain size, and number of molecular bonds at the interface and on the adhesion strength of the SiHA coating to the titanium substrate.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 6.2
DOI: 10.1016/J.SURFIN.2020.100727
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“Ab initio calculation of the interaction energy in the P2 binding pocket of HIV-1 protease”. Nivesanond K, Peeters A, Lamoen D, van Alsenoy C, International Journal Of Quantum Chemistry 105, 292 (2005). http://doi.org/10.1002/qua.20724
Keywords: A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Impact Factor: 2.92
Times cited: 8
DOI: 10.1002/qua.20724
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“Ab initio calculation of the energy-loss near-edge structure of some carbon allotropes: comparison with n-diamond”. Dadsetani M, Titantah JT, Lamoen D, Diamond and related materials 19, 73 (2010). http://doi.org/10.1016/j.diamond.2009.11.004
Abstract: The energy-loss near-edge structure (ELNES) spectra of several carbon allotropes (non-hydrogenated and hydrogenated face-centered cubic (FCC) carbon, rhombohedral carbon, glitter, hexagonite and lonsdaleite) are calculated within the supercell-core-excited density functional theory approach. In particular an experimental ELNES spectrum of new diamond (n-diamond) [Konyashin et al., Diamond Relat. Mater. 10, (2001) 99102] is compared with the ELNES spectra of FCC carbon, rhombohedral carbon and the so-called glitter structure. Our calculations show that the ELNES spectrum considered in that publication cannot be that of FCC carbon.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.561
Times cited: 11
DOI: 10.1016/j.diamond.2009.11.004
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“Ab initio based atomic scattering amplitudes and {002} electron structure factors of InxGa1-xAs/GaAs quantum wells”. Titantah JT, Lamoen D, Schowalter M, Rosenauer A, Journal of physics : conference series 209, 012040 (2010). http://doi.org/10.1088/1742-6596/209/1/012040
Abstract: The atomic scattering amplitudes of the various atoms of the systems Ga1−xInxAs, GaAs1−xNx and InAs1−xNx are calculated using the density functional theory (DFT) approach. The scattering amplitudes of N, Ga, As and In in the model systems are compared with the frequently used Doyle and Turner values. Deviation from the latter values is found for small scattering vectors (s<0.3Å−1) and for these scattering vectors dependence on the orientation of the scattering vector and the chemical environment is reported. We suggest a parametrization of these modified scattering amplitudes (MASAs) for small scattering vectors (s<1.0Å−1). The MASAs are exploited within zero pressure classical Metropolis Monte Carlo (MC), finite temperature calculations to investigate the effect of quantum well size on the electron {002} structure factor (SF) of Ga1−xInxAs quantum wells.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
DOI: 10.1088/1742-6596/209/1/012040
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“Ab initio approach to superexchange interactions in alkali doped fullerides AC60”. Nikolaev AV, Michel KH, AIP conference proceedings
T2 –, 18th International Winterschool/Euroconference on Electronic Properties, of Novel Materials, MAR 06-JUN 13, 2004, Kirchberg, AUSTRIA , 393 (2004). http://doi.org/10.1063/1.1812115
Abstract: The superexchange interactions between the fullerenes arise as a result of the electron transfer from the C-60 molecule to the alkali atom and back. We present a scheme, which is a configuration interaction approach based on the valence bond (Heitler-London) method. The effect of superexchange is described together with chemical bonding by constructing and solving a secular equation, rather than by using a perturbation treatment. We have considered 180degrees and 90degrees superexchange for the C-60 Cs-C-60 pathways. The calculations account for unusual electronic properties of polymer orthorhombic and quenched cubic phases of CsC60: two lines in nuclear magnetic resonance experiments, the development of a spin-singlet ground state and a decrease of magnetic susceptibility as T-->0.
Keywords: P1 Proceeding; Condensed Matter Theory (CMT)
DOI: 10.1063/1.1812115
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“Ab initio and semiempirical modeling of excitons and trions in monolayer TiS3”. Torun E, Sahin H, Chaves A, Wirtz L, Peeters FM, Physical review B 98, 075419 (2018). http://doi.org/10.1103/PHYSREVB.98.075419
Abstract: We explore the electronic and the optical properties of monolayer TiS3, which shows in-plane anisotropy and is composed of a chain-like structure along one of the lattice directions. Together with its robust direct band gap, which changes very slightly with stacking order and with the thickness of the sample, the anisotropic physical properties of TiS3 make the material very attractive for various device applications. In this study, we present a detailed investigation on the effect of the crystal anisotropy on the excitons and the trions of the TiS3 monolayer. We use many-body perturbation theory to calculate the absorption spectrum of anisotropic TiS3 monolayer by solving the Bethe-Salpeter equation. In parallel, we implement and use a Wannier-Mott model for the excitons that takes into account the anisotropic effective masses and Coulomb screening, which are obtained from ab initio calculations. This model is then extended for the investigation of trion states of monolayer TiS3. Our calculations indicate that the absorption spectrum of monolayer TiS3 drastically depends on the polarization of the incoming light, which excites different excitons with distinct binding energies. In addition, the binding energies of positively and the negatively charged trions are observed to be distinct and they exhibit an anisotropic probability density distribution.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 10
DOI: 10.1103/PHYSREVB.98.075419
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“AA-stacked bilayer square ice between graphene layers”. Sobrino Fernandez MM, Neek-Amal M, Peeters FM, Physical review : B : condensed matter and materials physics 92, 245428 (2015). http://doi.org/10.1103/PhysRevB.92.245428
Abstract: Water confined between two graphene layers with a separation of a few A forms a layered two-dimensional ice structure. Using large scale molecular dynamics simulations with the adoptable ReaxFF interatomic potential we found that flat monolayer ice with a rhombic-square structure nucleates between the graphene layers which is nonpolar and nonferroelectric. We provide different energetic considerations and H-bonding results that explain the interlayer and intralayer properties of two-dimensional ice. The controversial AA stacking found experimentally [Algara-Siller et al., Nature (London) 519, 443 (2015)] is consistent with our minimum-energy crystal structure of bilayer ice. Furthermore, we predict that an odd number of layers of ice has the same lattice structure as monolayer ice, while an even number of ice layers exhibits the square ice AA stacking of bilayer ice.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 40
DOI: 10.1103/PhysRevB.92.245428
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“A-site ordering versus electronic inhomogeneity in colossally magnetoresistive manganite films”. Moshnyaga V, Sudheendra L, Lebedev OI, Koster SA, Gehrke K, Shapoval O, Belenchuk A, Damaschke B, Van Tendeloo G, Samwer K, Physical review letters 97, 107205 (2006). http://doi.org/10.1103/PhysRevLett.97.107205
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 8.462
Times cited: 43
DOI: 10.1103/PhysRevLett.97.107205
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“A-site ordering and stripe phases in manganite films”. Sudheendra L, Moshnyaga V, Lebedev OI, Gehrke K, Belenciuc A, Shapoval O, Van Tendeloo G, Samwer K, Physica: B : condensed matter
T2 –, International Conference on Strongly Correlated Electron Systems (SCES, 2007), MAY 13-18, 2007, Houston, TX 403, 1645 (2008). http://doi.org/10.1016/j.physb.2007.10.332
Abstract: Insulating and metallic stripes above and below the Curie temperature, T-C, respectively, were observed by a high-resolution scanning tunneling microscopy (STM) and/or spectroscopy (STS) in A-site ordered and macroscopically strain free epitaxial La0.75Ca0.25MnO3 film grown on MgO substrate. The “insulating” stripes were found to be incommensurable to the lattice and aligned along (110) direction. Metallic stripes were commensurable with periodicity 2a(p)similar to 0.8 nm and aligned parallel to the crystallographic a/b-axis. Formation of these stripes involves competing charge, orbital, and lattice orders and is an outcome of an overlapping of electron wave functions mediated by the local lattice-strain distribution, existed even in A-site ordered film due to the difference in cation radii of La and Ca. (C) 2007 Elsevier B.V. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.386
DOI: 10.1016/j.physb.2007.10.332
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“A XANES study of chromophores : the case of black glass”. Ceglia A, Nuyts G, Cagno S, Meulebroeck W, Baert K, Cosyns P, Nys K, Thienpont H, Janssens K, Terryn H, Analytical methods 6, 2662 (2014). http://doi.org/10.1039/C3AY42029A
Abstract: We studied the Fe K-edge X-ray absorption near edge (XANES) spectra of several Roman black glass fragments in order to determine the Fe3+/ΣFe ratio of these materials. The selected archaeological glass samples cover the period 1st5th century AD in nine different sites of the North Western provinces of the Roman Empire. The fragments belong to two different compositional groups demonstrating a diachronic evolution: early Roman HMG (High Magnesia Glass) and Roman Imperial LMG (Low Magnesia Glass). The first group contains natural Fe levels (below 2 wt% as Fe2O3), while the LMG has concentrations above 5 wt%. This difference is also reflected by Fe3+/ΣFe values. Low iron glass was produced under strongly reducing conditions in order to obtain the black colour, with average Fe3+/ΣFe values ≈ 0.17. LMG glass is somewhat more oxidised (Fe3+/ΣFe ≈ 0.40.5). While HMG glass required active control of the furnace environment, LMG was made under ambient atmosphere and its higher oxidation degree is mainly determined by the chemistry of the raw glass.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 1.9
Times cited: 14
DOI: 10.1039/C3AY42029A
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“A weak compatibility condition for precipitation with application to the microstructure of PbTe-Sb2Te3 thermoelectrics”. Chen X, Cao S, Ikeda T, Srivastava V, Snyder GJ, Schryvers D, James RD, Acta materialia 59, 6124 (2011). http://doi.org/10.1016/j.actamat.2011.06.025
Abstract: We propose a weak condition of compatibility between phases applicable to cases exhibiting full or partial coherence and Widmanstätten microstructure. The condition is applied to the study of Sb2Te3 precipitates in a PbTe matrix in a thermoelectric alloy. The weak condition of compatibility predicts elongated precipitates lying on a cone determined by a transformation stretch tensor. Comparison of this cone with the long directions of precipitates determined by a slice-and-view method of scanning electron microscopy combined with focused ion beam sectioning shows good agreement between theory and experiment. A further study of the morphology of precipitates by the Eshelby method suggests that interfacial energy also plays a role and gives an approximate value of interfacial energy per unit area of 250 dyn cm−1.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 5.301
Times cited: 8
DOI: 10.1016/j.actamat.2011.06.025
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“A versatile plasma tool for the synthesis of carbon nanotubes and few-layer graphene sheets”. Malesevic A, Kemps R, Zhang L, Erni R, Van Tendeloo G, Vanhulsel A, van Haesendonck C, Journal of optoelectronics and advanced materials 10, 2052 (2008)
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 0.449
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“A versatile lab-on-chip test platform to characterize elementary deformation mechanisms and electromechanical couplings in nanoscopic objects”. Pardoen T, Colla M-S, Idrissi H, Amin-Ahmadi B, Wang B, Schryvers D, Bhaskar UK, Raskin J-P, Comptes rendus : physique 17, 485 (2016). http://doi.org/10.1016/j.crhy.2015.11.005
Abstract: A nanomechanical on-chip test platform has recently been developed to deform under a variety of loading conditions freestanding thin films, ribbons and nanowires involving submicron dimensions. The lab-on-chip involves thousands of elementary test structures from which the elastic modulus, strength, strain hardening, fracture, creep properties can be extracted. The technique is amenable to in situ transmission electron microscopy (TEM) investigations to unravel the fundamental underlying deformation and fracture mechanisms that often lead to size-dependent effects in small-scale samples. The method allows addressing electrical and magnetic couplings as well in order to evaluate the impact of large mechanical stress levels on different solid-state physics phenomena. We had the chance to present this technique in details to Jacques Friedel in 2012 who, unsurprisingly, made a series of critical and very relevant suggestions. In the spirit of his legacy, the paper will address both mechanics of materials related phenomena and couplings with solids state physics issues.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.048
Times cited: 7
DOI: 10.1016/j.crhy.2015.11.005
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