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Author Zieliński, P.; Michel, K.H.
  Title Microscopic model of surfaces in orientationally disordered ionic crystals : the (001) surface of KCN Type A1 Journal article
  Year 1992 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 46 Issue 8 Pages 4806-4815
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The crystallographic structure and the distribution of orientations of molecular ions are studied near the surface in an orientationally disordered crystal with the use of a Green-function formalism. The orientational degrees of freedom are treated by means of symmetry-adapted functions of angular coordinates. The structure of the (001) surface of KCN in its cubic fcc phase is then predicted using the existing data on the interaction of the ions K+ and CN-. A local antiferroelectric and antiferroelastic order i shown to exist in the surface region. The magnitude of the order and the spatial extent of the ordered re ion increase as the temperature approaches the point of the phase transition to the ordered phase. The,influence of the external electric field on the structure of the surface is predicted.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos (down) A1992JK72500049 Publication Date 2002-07-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.736 Times cited 4 Open Access
  Notes Approved PHYSICS, CONDENSED MATTER 16/67 Q1 #
  Call Number UA @ lucian @ c:irua:2974 Serial 2029
Permanent link to this record
 

 
Author Peeters, F.M.; Vasilopoulos, P.
  Title Electrical and thermal-properties of a 2-dimensional electron-gas in a one-dimensional periodic potential Type A1 Journal article
  Year 1992 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 46 Issue 8 Pages 4667-4680
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We investigate the influence of a periodic weak modulation along the x direction on the electrical and thermal properties of a two-dimensional electron gas in the presence of a perpendicular magnetic field. The modulation lifts the degeneracy of the Landau levels and leads to one-dimensional magnetic bands whose bandwidth oscillates as a function of the magnetic field. At weak magnetic fields this gives rise to the Weiss oscillations in the magnetoresistance, discovered recently, which have a very weakly temperature-dependent amplitude and a period proportional to square-root n(e), when n(e) is the electron density. Diffusion-current contributions, proportional to the square of the bandwidth, dominate rho(xx), and collisional contributions, varying approximately as the square of the density of states, dominate rho(yy). The result is that rho(xx) and rho(yy) oscillate out of phase as observed. Asymptotic analytical expressions are presented for the conductivity tensor. Similar oscillations, of much smaller amplitude, occur in the thermodynamic quantities, such as the magnetization, the susceptibility, and the specific heat. We also predict oscillations in the Hall resistance, the cyclotron resonance position, the linewidth, as well as in the thermal conductivity and thermopower. The components of the thermal-resistance tensor have a magnetic-field dependence similar to that of the electrical-resistivity tensor.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos (down) A1992JK72500032 Publication Date 2002-07-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.736 Times cited 148 Open Access
  Notes Approved INSTRUMENTS & INSTRUMENTATION 31/56 Q3 # NUCLEAR SCIENCE & TECHNOLOGY 9/32 Q2 # PHYSICS, PARTICLES & FIELDS 24/28 Q4 # SPECTROSCOPY 28/43 Q3 #
  Call Number UA @ lucian @ c:irua:103028 Serial 889
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Author Backes, W.H.; Peeters, F.M.; Brosens, F.; Devreese, J.T.
  Title Dispersion of longitudinal plasmons for a quasi-two-dimensional electron gas Type A1 Journal article
  Year 1992 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 45 Issue 15 Pages 8437-8442
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
  Abstract Confinement of electrons in ultrathin metallic films leads to subbands. By increasing the thickness of the electron layer, the subbands will dissolve into a quasicontinuum, with the number of electrons per unit volume kept constant. Within the random-phase approximation, the two-dimensional plasmon, which originally follows Stern's dispersion relation, becomes a longitudinal surface plasmon. The plasmon excitations of a model metallic film are investigated by including all subbands. Single-particle excitations, which exhibit the depolarization shift, converge into the plasma excitation spectrum. With further increases in the film thickness, the bulk plasmon arises and the surface plasmon remains. Our analysis shows how quantum size effects evolve into hydrodynamical classical size effects with increasing thickness of the film.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos (down) A1992HR33600028 Publication Date 2002-07-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.736 Times cited 37 Open Access
  Notes Approved no
  Call Number UA @ lucian @ c:irua:2738 Serial 737
Permanent link to this record
 

 
Author Verbist, G.; Smondyrev, M.A.; Peeters, F.M.; Devreese, J.T.
  Title Strong-coupling analysis of large bipolarons in 2 and 3 dimensions Type A1 Journal article
  Year 1992 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 45 Issue 10 Pages 5262-5269
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
  Abstract In the limit of strong electron-phonon coupling, we use either a Pekar-type or an oscillator wave function for the center-of-mass coordinate and either a Coulomb or an oscillator wave function for the relative coordinate, and are able to reproduce all the results from the literature for the large-bipolaron binding energy. Lower bounds are constructed for the critical ratio eta(c) of dielectric constants below which bipolarons can exist. It is found that, in the strong-coupling limit, the stability region for bipolaron formation is much larger in two dimensions (2D) than in 3D. We introduce a model that combines the averaging of the relative coordinate over the asymptotically best wave function with a path-integral treatment of the center-of-mass motion. The stability region for bipolaron formation is increased compared with the full path-integral treatment at large values of the coupling constant alpha. The critical values are alpha(c) almost-equal-to 9.3 in 3D and alpha(c) almost-equal-to 4.5 in 2D. Phase diagrams for the presented models are also obtained in both 2D and 3D.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos (down) A1992HJ68900016 Publication Date 2002-07-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.736 Times cited 68 Open Access
  Notes Approved PHYSICS, APPLIED 28/145 Q1 #
  Call Number UA @ lucian @ c:irua:103051 Serial 3178
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Author Verbist, G.; Smondyrev, M.A.; Peeters, F.M.; Devreese, J.T.
  Title Strong-coupling analysis of large bipolarons in two and three dimensions Type A1 Journal article
  Year 1992 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 45 Issue Pages 5262-5269
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) A1992HJ68900016 Publication Date 2002-07-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0163-1829 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.736 Times cited 68 Open Access
  Notes Approved PHYSICS, APPLIED 28/145 Q1 #
  Call Number UA @ lucian @ c:irua:2891 Serial 3179
Permanent link to this record
 

 
Author Tanner, L.E.; Shapiro, S.M.; Schryvers, D.; Noda, Y.
  Title Review of phonon behaviour and microstructural development leading to martensitic transformations in NixAl100-x alloys Type A3 Journal article
  Year 1992 Publication Shape memory materials and phenomena: fundamental aspects and applications Abbreviated Journal
  Volume 246 Issue Pages 265-276
  Keywords A3 Journal article; Electron microscopy for materials research (EMAT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) A1992BW94E00038 Publication Date 0000-00-00
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor Times cited 4 Open Access
  Notes Approved MATERIALS SCIENCE, MULTIDISCIPLINARY 96/271 Q2 #
  Call Number UA @ lucian @ c:irua:4368 Serial 2904
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Author Schryvers, D.; Tanner, L.E.
  Title Electron microscopy of stress-induced martensite and pretransition microstructures in Ni62.5Al37.5 Type A3 Journal article
  Year 1992 Publication Shape memory materials and phenomena: fundamental aspects and applications Abbreviated Journal
  Volume 246 Issue Pages 33-38
  Keywords A3 Journal article; Electron microscopy for materials research (EMAT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) A1992BW94E00005 Publication Date 0000-00-00
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor Times cited 5 Open Access
  Notes Approved CHEMISTRY, PHYSICAL 54/144 Q2 # PHYSICS, ATOMIC, MOLECULAR & CHEMICAL 9/35 Q2 #
  Call Number UA @ lucian @ c:irua:4367 Serial 964
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Author Shapiro, S.M.; Yang, B.X.; Noda, Y.; Tanner, L.E.; Schryvers, D.
  Title Neutron-scattering and electron microscopy studies of premartensitic phenomena in NixAl100-x alloys Type A1 Journal article
  Year 1991 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 44 Issue Pages 9301-9313
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos (down) A1991GP26700019 Publication Date 0000-00-00
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121; 0163-1829 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.736 Times cited 123 Open Access
  Notes Approved MATERIALS SCIENCE, MULTIDISCIPLINARY 96/271 Q2 #
  Call Number UA @ lucian @ c:irua:48351 Serial 2299
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Author Worlock, J.M.; Peeters, F.M.; Cox, H.M.; Morais, P.C.
  Title Quantum-wire spectroscopy and epitaxial-growth velocities in InxGa1-xAs-InP heterostructures Type A1 Journal article
  Year 1991 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 44 Issue Pages 8923-8926
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos (down) A1991GN30400057 Publication Date 0000-00-00
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121; 0163-1829 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.736 Times cited 12 Open Access
  Notes Approved no
  Call Number UA @ lucian @ c:irua:941 Serial 2797
Permanent link to this record
 

 
Author Shi, J.M.; Peeters, F.M.; Hai, G.Q.; Devreese, J.T.
  Title Donor transition energy in GaAs-superlattices in a magnetic field along the growth axis Type A1 Journal article
  Year 1991 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 44 Issue Pages 5692-5702
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos (down) A1991GF44300042 Publication Date 0000-00-00
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121; 0163-1829 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.736 Times cited 78 Open Access
  Notes Approved no
  Call Number UA @ lucian @ c:irua:915 Serial 749
Permanent link to this record
 

 
Author Xu, W.; Peeters, F.M.; Devreese, J.T.
  Title Diffusion-to-streaming transition in a two-dimensional electron system in a polar semiconductor Type A1 Journal article
  Year 1991 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 43 Issue Pages 14134-14141
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos (down) A1991FQ97400035 Publication Date 0000-00-00
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121; 0163-1829 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.736 Times cited 24 Open Access
  Notes Approved no
  Call Number UA @ lucian @ c:irua:913 Serial 701
Permanent link to this record
 

 
Author Helm, M.; Peeters, F.M.; DeRosa, F.; Colas, E.; Harbison, J.P.; Florez, L.T.
  Title Far-infrared spectroscopy of minibands and confined donors in GaAs/AlxGa1-xAs superlattices Type A1 Journal article
  Year 1991 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 43 Issue Pages 13983-13991
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos (down) A1991FQ97400019 Publication Date 0000-00-00
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121; 0163-1829 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.736 Times cited 77 Open Access
  Notes Approved no
  Call Number UA @ lucian @ c:irua:949 Serial 1174
Permanent link to this record
 

 
Author Verbist, G.; Peeters, F.M.; Devreese, J.T.
  Title Large bipolarons in three and two dimensions Type A1 Journal article
  Year 1991 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 43 Issue Pages 2712-2720
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos (down) A1991FF08300030 Publication Date 0000-00-00
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121; 0163-1829 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.736 Times cited 155 Open Access
  Notes Approved no
  Call Number UA @ lucian @ c:irua:911 Serial 1779
Permanent link to this record
 

 
Author Peeters, F.M.; Golub, J.E.
  Title Binding energy of the barbell exciton Type A1 Journal article
  Year 1991 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 43 Issue Pages 5159-5162
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos (down) A1991EY62300076 Publication Date 0000-00-00
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121; 0163-1829 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.736 Times cited 27 Open Access
  Notes Approved no
  Call Number UA @ lucian @ c:irua:955 Serial 239
Permanent link to this record
 

 
Author Peeters, F.M.; Smondyrev, M.A.
  Title Exact and approximate results for the polaron in one dimension Type A1 Journal article
  Year 1991 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 43 Issue Pages 4920-4924
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos (down) A1991EY62300044 Publication Date 0000-00-00
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121; 0163-1829 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.736 Times cited 16 Open Access
  Notes Approved no
  Call Number UA @ lucian @ c:irua:963 Serial 1104
Permanent link to this record
 

 
Author Bostoen, C.; Michel, K.H.
  Title Dynamics of a quadrupolar glass Type A1 Journal article
  Year 1991 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 43 Issue Pages 4415-4422
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos (down) A1991EX92100073 Publication Date 0000-00-00
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121; 0163-1829 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.736 Times cited 33 Open Access
  Notes Approved no
  Call Number UA @ lucian @ c:irua:939 Serial 773
Permanent link to this record
 

 
Author Schryvers, D.; de Saegher, B.; van Landuyt, J.
  Title Electron microscopy and diffraction study of the composition dependency of the 3R microtwinned martensite in Ni-Al Type A1 Journal article
  Year 1991 Publication Materials research bulletin Abbreviated Journal Mater Res Bull
  Volume 26 Issue Pages 57-66
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication New York, N.Y. Editor
  Language Wos (down) A1991EU98500007 Publication Date 0000-00-00
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0025-5408 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.288 Times cited 11 Open Access
  Notes Approved no
  Call Number UA @ lucian @ c:irua:48348 Serial 943
Permanent link to this record
 

 
Author Xu, H.; Li, H.; Gauquelin, N.; Chen, X.; Wu, W.-F.; Zhao, Y.; Si, L.; Tian, D.; Li, L.; Gan, Y.; Qi, S.; Li, M.; Hu, F.; Sun, J.; Jannis, D.; Yu, P.; Chen, G.; Zhong, Z.; Radovic, M.; Verbeeck, J.; Chen, Y.; Shen, B.
  Title Giant tunability of Rashba splitting at cation-exchanged polar oxide interfaces by selective orbital hybridization Type A1 Journal article
  Year 2024 Publication Advanced materials Abbreviated Journal
  Volume Issue Pages
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract The 2D electron gas (2DEG) at oxide interfaces exhibits extraordinary properties, such as 2D superconductivity and ferromagnetism, coupled to strongly correlated electrons in narrow d-bands. In particular, 2DEGs in KTaO3 (KTO) with 5d t2g orbitals exhibit larger atomic spin-orbit coupling and crystal-facet-dependent superconductivity absent for 3d 2DEGs in SrTiO3 (STO). Herein, by tracing the interfacial chemistry, weak anti-localization magneto-transport behavior, and electronic structures of (001), (110), and (111) KTO 2DEGs, unambiguously cation exchange across KTO interfaces is discovered. Therefore, the origin of the 2DEGs at KTO-based interfaces is dramatically different from the electronic reconstruction observed at STO interfaces. More importantly, as the interface polarization grows with the higher order planes in the KTO case, the Rashba spin splitting becomes maximal for the superconducting (111) interfaces approximately twice that of the (001) interface. The larger Rashba spin splitting couples strongly to the asymmetric chiral texture of the orbital angular moment, and results mainly from the enhanced inter-orbital hopping of the t2g bands and more localized wave functions. This finding has profound implications for the search for topological superconductors, as well as the realization of efficient spin-charge interconversion for low-power spin-orbitronics based on (110) and (111) KTO interfaces. An unambiguous cation exchange is discovered across the interfaces of (001), (110), and (111) KTaO3 2D electron gases fabricated at room temperature. Remarkably, the (111) interfaces with the highest superconducting transition temperature also turn out to show the strongest electron-phonon interaction and the largest Rashba spin splitting. image
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 001219658400001 Publication Date 2024-03-13
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0935-9648 ISBN Additional Links UA library record; WoS full record
  Impact Factor 29.4 Times cited Open Access
  Notes Approved Most recent IF: 29.4; 2024 IF: 19.791
  Call Number UA @ admin @ c:irua:206037 Serial 9152
Permanent link to this record
 

 
Author Hassani, N.; Movafegh-Ghadirli, A.; Mahdavifar, Z.; Peeters, F.M.; Neek-Amal, M.
  Title Two new members of the covalent organic frameworks family : crystalline 2D-oxocarbon and 3D-borocarbon structures Type A1 Journal article
  Year 2024 Publication Computational materials science Abbreviated Journal
  Volume 241 Issue Pages 1-9
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Oxocarbons, known for over two centuries, have recently revealed a long-awaited facet: two-dimensional crystalline structures. Employing an intelligent global optimization algorithm (IGOA) alongside densityfunctional calculations, we unearthed a quasi -flat oxocarbon (C 6 0 6 ), featuring an oxygen -decorated hole, and a novel 3D-borocarbon. Comparative analyses with recently synthesized isostructures, such as 2D -porous carbon nitride (C 6 N 6 ) and 2D -porous boroxine (B 6 0 6 ), highlight the unique attributes of these compounds. All structures share a common stoichiometry of X 6 Y 6 (which we call COF-66), where X = B, C, and Y = B, N, O (with X not equal Y), exhibiting a 2D -crystalline structure, except for borocarbon C 6 B 6 , which forms a 3D crystal. In our comprehensive study, we conducted a detailed exploration of the electronic structure of X 6 Y 6 compounds, scrutinizing their thermodynamic properties and systematically evaluating phonon stability criteria. With expansive surface areas, diverse pore sizes, biocompatibility, pi-conjugation, and distinctive photoelectric properties, these structures, belonging to the covalent organic framework (COF) family, present enticing prospects for fundamental research and hold potential for biosensing applications.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 001215960700001 Publication Date 2024-04-23
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0927-0256 ISBN Additional Links UA library record; WoS full record
  Impact Factor 3.3 Times cited Open Access
  Notes Approved Most recent IF: 3.3; 2024 IF: 2.292
  Call Number UA @ admin @ c:irua:206005 Serial 9179
Permanent link to this record
 

 
Author Yorulmaz, U.; Šabani, D.; Sevik, C.; Milošević, M.V.
  Title Goodenough-Kanamori-Anderson high-temperature ferromagnetism in tetragonal transition-metal xenes Type A1 Journal article
  Year 2024 Publication 2D materials Abbreviated Journal
  Volume 11 Issue 3 Pages 035013-10
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Seminal Goodenough-Kanamori-Anderson (GKA) rules provide an inceptive understanding of the superexchange interaction of two magnetic metal ions bridged with an anion, and suggest fostered ferromagnetic interaction for orthogonal bridging bonds. However, there are no examples of two-dimensional (2D) materials with structure that optimizes the GKA arguments towards enhanced ferromagnetism and its critical temperature. Here we reveal that an ideally planar GKA ferromagnetism is indeed stable in selected tetragonal transition-metal xenes (tTMXs), with Curie temperature above 300 K found in CrC and MnC. We provide the general orbitally-resolved analysis of magnetic interactions that supports the claims and sheds light at the mechanisms dominating the magnetic exchange process in these structures. Furthermore, we propose the set of three GKA-like rules that will guarantee room temperature ferromagetnism. With recent advent of epitaxially-grown tetragonal 2D materials, our findings earmark tTMXs for facilitated spintronic and magnonic applications, or as a desirable magnetic constituent of functional 2D heterostructures.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 001208053200001 Publication Date 2024-04-12
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2053-1583 ISBN Additional Links UA library record; WoS full record
  Impact Factor 5.5 Times cited Open Access
  Notes Approved Most recent IF: 5.5; 2024 IF: 6.937
  Call Number UA @ admin @ c:irua:205464 Serial 9153
Permanent link to this record
 

 
Author Chakraborty, J.; Chatterjee, A.; Molkens, K.; Nath, I.; Arenas Esteban, D.; Bourda, L.; Watson, G.; Liu, C.; Van Thourhout, D.; Bals, S.; Geiregat, P.; Van der Voort, P.
  Title Decoding Excimer Formation in Covalent–Organic Frameworks Induced by Morphology and Ring Torsion Type A1 Journal Article
  Year 2024 Publication Advanced Materials Abbreviated Journal Advanced Materials
  Volume Issue Pages
  Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
  Abstract A thorough and quantitative understanding of the fate of excitons in covalent–organic frameworks (COFs) after photoexcitation is essential for their augmented optoelectronic and photocatalytic applications via precise structure tuning. The synthesis of a library of COFs having identical chemical backbone with impeded conjugation, but varied morphology and surface topography to study the effect of these physical properties on the photophysics of the materials is herein reported. The variation of crystallite size and surface topography substantified different aggregation pattern in the COFs, which leads to disparities in their photoexcitation and relaxation properties. Depending on aggregation, an inverse correlation between bulk luminescence decay time and exciton binding energy of the materials is perceived. Further transient absorption spectroscopic analysis confirms the presence of highly localized, immobile, Frenkel excitons (of diameter 0.3–0.5 nm) via an absence of annihilation at high density, most likely induced by structural torsion of the COF skeletons, which in turn preferentially relaxes via long‐lived (nanosecond to microsecond) excimer formation (in femtosecond scale) over direct emission. These insights underpin the importance of structural and topological design of COFs for their targeted use in photocatalysis.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 001206226700001 Publication Date 2024-04-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0935-9648 ISBN Additional Links UA library record; WoS full record
  Impact Factor 29.4 Times cited Open Access
  Notes PVDV, JC, AC, and IN acknowledge the FWO-Vlaanderen for research grant G020521N and the research board of UGent (BOF) through a Concerted Research Action (GOA010-17). JC acknowledges UGent for BOF postdoctoral grant (2022.0032.01). AC acknowledges FWO- Vlaanderen for postdoctoral grant (12T7521N). KM, DVT and PG acknowledges FWO- Vlaanderen for research grant G0B2921N. SB and DAE acknowledge financial support from ERC Consolidator Grant Number 815128 REALNANO. CHL acknowledges China Scholarship Council doctoral grant (201908110280). PVDV acknowledges Hercules Project AUGE/17/07 for the UV VIS DRS spectrometer and UGent BASBOF BOF20/BAS/015 for the powder X-Ray Diffractometer. PG thanks UGent for support of the Core Facility NOLIMITS. Approved Most recent IF: 29.4; 2024 IF: 19.791
  Call Number EMAT @ emat @c:irua:205967 Serial 9118
Permanent link to this record
 

 
Author Chakraborty, J.; Chatterjee, A.; Molkens, K.; Nath, I.; Arenas Esteban, D.; Bourda, L.; Watson, G.; Liu, C.; Van Thourhout, D.; Bals, S.; Geiregat, P.; Van der Voort, P.
  Title Decoding Excimer Formation in Covalent–Organic Frameworks Induced by Morphology and Ring Torsion Type A1 Journal Article
  Year 2024 Publication Advanced Materials Abbreviated Journal Advanced Materials
  Volume Issue Pages
  Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
  Abstract A thorough and quantitative understanding of the fate of excitons in covalent–organic frameworks (COFs) after photoexcitation is essential for their augmented optoelectronic and photocatalytic applications via precise structure tuning. The synthesis of a library of COFs having identical chemical backbone with impeded conjugation, but varied morphology and surface topography to study the effect of these physical properties on the photophysics of the materials is herein reported. The variation of crystallite size and surface topography substantified different aggregation pattern in the COFs, which leads to disparities in their photoexcitation and relaxation properties. Depending on aggregation, an inverse correlation between bulk luminescence decay time and exciton binding energy of the materials is perceived. Further transient absorption spectroscopic analysis confirms the presence of highly localized, immobile, Frenkel excitons (of diameter 0.3–0.5 nm) via an absence of annihilation at high density, most likely induced by structural torsion of the COF skeletons, which in turn preferentially relaxes via long‐lived (nanosecond to microsecond) excimer formation (in femtosecond scale) over direct emission. These insights underpin the importance of structural and topological design of COFs for their targeted use in photocatalysis.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 001206226700001 Publication Date 2024-04-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0935-9648 ISBN Additional Links UA library record; WoS full record
  Impact Factor 29.4 Times cited Open Access
  Notes PVDV, JC, AC, and IN acknowledge the FWO-Vlaanderen for research grant G020521N and the research board of UGent (BOF) through a Concerted Research Action (GOA010-17). JC acknowledges UGent for BOF postdoctoral grant (2022.0032.01). AC acknowledges FWOVlaanderen for postdoctoral grant (12T7521N). KM, DVT and PG acknowledges FWOVlaanderen for research grant G0B2921N. SB and DAE acknowledge financial support from ERC Consolidator Grant Number 815128 REALNANO. CHL acknowledges China Scholarship Council doctoral grant (201908110280). PVDV acknowledges Hercules Project AUGE/17/07 for the UV VIS DRS spectrometer and UGent BASBOF BOF20/BAS/015 for the powder X-Ray Diffractometer. PG thanks UGent for support of the Core Facility NOLIMITS. Approved Most recent IF: 29.4; 2024 IF: 19.791
  Call Number EMAT @ emat @c:irua:205967 Serial 9130
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Author Wu, X.; Ding, J.; Cui, W.; Lin, W.; Xue, Z.; Yang, Z.; Liu, J.; Nie, X.; Zhu, W.; Van Tendeloo, G.; Sang, X.
  Title Enhanced electrical properties of Bi2-xSbxTe3 nanoflake thin films through interface engineering Type A1 Journal article
  Year 2024 Publication Energy & environment materials Abbreviated Journal
  Volume Issue Pages e12755-8
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract The structure-property relationship at interfaces is difficult to probe for thermoelectric materials with a complex interfacial microstructure. Designing thermoelectric materials with a simple, structurally-uniform interface provides a facile way to understand how these interfaces influence the transport properties. Here, we synthesized Bi2-xSbxTe3 (x = 0, 0.1, 0.2, 0.4) nanoflakes using a hydrothermal method, and prepared Bi2-xSbxTe3 thin films with predominantly (0001) interfaces by stacking the nanoflakes through spin coating. The influence of the annealing temperature and Sb content on the (0001) interface structure was systematically investigated at atomic scale using aberration-corrected scanning transmission electron microscopy. Annealing and Sb doping facilitate atom diffusion and migration between adjacent nanoflakes along the (0001) interface. As such it enhances interfacial connectivity and improves the electrical transport properties. Interfac reactions create new interfaces that increase the scattering and the Seebeck coefficient. Due to the simultaneous optimization of electrical conductivity and Seebeck coefficient, the maximum power factor of the Bi1.8Sb0.2Te3 nanoflake films reaches 1.72 mW m(-1) K-2, which is 43% higher than that of a pure Bi2Te3 thin film.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 001204495900001 Publication Date 2024-04-18
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor Times cited Open Access
  Notes Approved Most recent IF: NA
  Call Number UA @ admin @ c:irua:205438 Serial 9148
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Author Ignatova, K.; Vlasov, E.; Seddon, S.D.; Gauquelin, N.; Verbeeck, J.; Wermeille, D.; Bals, S.; Hase, T.P.A.; Arnalds, U.B.
  Title Phase coexistence induced surface roughness in V2O3/Ni magnetic heterostructures Type A1 Journal Article
  Year 2024 Publication APL Materials Abbreviated Journal
  Volume 12 Issue 4 Pages
  Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
  Abstract We present an investigation of the microstructure changes in V2O3 as it goes through its inherent structural phase transition. Using V2O3 films with a well-defined crystal structure deposited by reactive magnetron sputtering on r-plane Al2O3 substrates, we study the phase coexistence region and its impact on the surface roughness of the films and the magnetic properties of overlying Ni magnetic layers in V2O3/Ni hybrid magnetic heterostructures. The simultaneous presence of two phases in V2O3 during its structural phase transition was identified with high resolution x-ray diffraction and led to an increase in surface roughness observed using x-ray reflectivity. The roughness reaches its maximum at the midpoint of the transition. In V2O3/Ni hybrid heterostructures, we find a concomitant increase in the coercivity of the magnetic layer correlated with the increased roughness of the V2O3 surface. The chemical homogeneity of the V2O3 is confirmed through transmission electron microscopy analysis. High-angle annular dark field imaging and electron energy loss spectroscopy reveal an atomically flat interface between Al2O3 and V2O3, as well as a sharp interface between V2O3 and Ni.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 001202661800003 Publication Date 2024-04-01
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2166-532X ISBN Additional Links UA library record; WoS full record
  Impact Factor 6.1 Times cited Open Access
  Notes This work was supported by the funding from the University of Iceland Research Fund, the Icelandic Research Fund Grant No. 207111. Instrumentation funding from the Icelandic Infrastructure Fund is acknowledged. This work was based on experiments per- formed at the BM28 (XMaS) beamline at the European Synchrotron Radiation Facility, Grenoble, France. XMaS is a National Research Facility funded by the UK EPSRC and managed by the Universi- ties of Liverpool and Warwick. This project has received funding from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 823717—ESTEEM3. Approved Most recent IF: 6.1; 2024 IF: 4.335
  Call Number EMAT @ emat @c:irua:205569 Serial 9120
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Author Yang, C.-Q.; Yin, Z.-W.; Li, W.; Cui, W.-J.; Zhou, X.-G.; Wang, L.-D.; Zhi, R.; Xu, Y.-Y.; Tao, Z.-W.; Sang, X.; Cheng, Y.-B.; Van Tendeloo, G.; Hu, Z.-Y.; Su, B.-L.
  Title Atomically deciphering the phase segregation in mixed halide perovskite Type A1 Journal article
  Year 2024 Publication Advanced functional materials Abbreviated Journal
  Volume Issue Pages 1-10
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Mixed-halide perovskites show promising applications in tandem solar cells owing to their adjustable bandgap. One major obstacle to their commercialization is halide phase segregation, which results in large open-circuit voltage deficiency and J-V hysteresis. However, the ambiguous interplay between structural origin and phase segregation often results in aimless and unspecific optimization strategies for the device's performance and stability. An atomic scale is directly figured out the abundant Ruddlesden-Popper anti-phase boundaries (RP-APBs) within a CsPbIBr2 polycrystalline film and revealed that phase segregation predominantly occurs at RP-APB-enriched interfaces due to the defect-mediated lattice strain. By compensating their structural lead halide, such RP-APBs are eliminated, and the decreasing of strain can be observed, resulting in the suppression of halide phase segregation. The present work provides the deciphering to precisely regulate the perovskite atomic structure for achieving photo-stable mixed halide wide-bandgap perovskites of high-efficiency tandem solar cell commercial applications. The phase segregation in mixed halide perovskite film predominantly occurs at Ruddlesden-Popper anti-phase boundaries (RP-APBs)-enriched interfaces due to the defect-mediated lattice strain. The RP-APBs defects can be eliminated by compensating for their structural lead halide deficiency, resulting in the suppression of halide phase segregation. image
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 001200673300001 Publication Date 2024-04-12
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1616-301x ISBN Additional Links UA library record; WoS full record
  Impact Factor 19 Times cited Open Access
  Notes Approved Most recent IF: 19; 2024 IF: 12.124
  Call Number UA @ admin @ c:irua:205509 Serial 9134
Permanent link to this record
 

 
Author Kashiwar, A.; Arseenko, M.; Simar, A.; Idrissi, H.
  Title On the role of microstructural defects on precipitation, damage, and healing behavior in a novel Al-0.5Mg2Si alloy Type A1 Journal article
  Year 2024 Publication Materials & design Abbreviated Journal
  Volume 239 Issue Pages 112765-112769
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract A recently developed healable Al-Mg2Si designed by the programmed damage and repair (PDR) strategy is studied considering the role microstructural defects play on precipitation, damage, and healing. The alloy incorporates sacrificial Mg2Si particles that precipitate after friction stir processing (FSP). They act as damage localization sites and are healable based on the solid-state diffusion of Al-matrix. A combination of different transmission electron microscopy (TEM) imaging techniques enabled the visualization and quantification of various crystallographic defects and the spatial distribution of Mg2Si precipitates. Intragrain nucleation is found to be the dominant mechanism for precipitation during FSP whereas grain boundaries and subgrain boundaries mainly lead to coarsening of the precipitates. The statistical and spatial analyses of the damaged particles have shown particle fracture as the dominant damage mechanism which is strongly dependent on the size and aspect ratio of the particles whereas the damage was not found to depend on the location of the precipitates within the matrix. The damaged particles are associated with dislocations accumulated around them. The interplay of these dislocations is directly visualized during healing based on in situ TEM heating which revealed recovery in the matrix as an operative mechanism during the diffusion healing of the PDR alloy.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 001194110200001 Publication Date 2024-02-17
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0264-1275; 1873-4197 ISBN Additional Links UA library record; WoS full record
  Impact Factor 8.4 Times cited Open Access Not_Open_Access
  Notes Approved Most recent IF: 8.4; 2024 IF: 4.364
  Call Number UA @ admin @ c:irua:203298 Serial 9068
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Author Arisnabarreta, N.; Hao, Y.; Jin, E.; Salame, A.; Muellen, K.; Robert, M.; Lazzaroni, R.; Van Aert, S.; Mali, K.S.; De Feyter, S.
  Title Single-layered imine-linked porphyrin-based two-dimensional covalent organic frameworks targeting CO₂ reduction Type A1 Journal article
  Year 2024 Publication Advanced energy materials Abbreviated Journal
  Volume Issue Pages
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract The reduction of carbon dioxide (CO2) using porphyrin-containing 2D covalent organic frameworks (2D-COFs) catalysts is widely explored nowadays. While these framework materials are normally fabricated as powders followed by their uncontrolled surface heterogenization or directly grown as thin films (thickness >200 nm), very little is known about the performance of substrate-supported single-layered (approximate to 0.5 nm thickness) 2D-COFs films (s2D-COFs) due to its highly challenging synthesis and characterization protocols. In this work, a fast and straightforward fabrication method of porphyrin-containing s2D-COFs is demonstrated, which allows their extensive high-resolution visualization via scanning tunneling microscopy (STM) in liquid conditions with the support of STM simulations. The as-prepared single-layered film is then employed as a cathode for the electrochemical reduction of CO2. Fe porphyrin-containing s2D-COF@graphite used as a single-layered heterogeneous catalyst provided moderate-to-high carbon monoxide selectivity (82%) and partial CO current density (5.1 mA cm(-2)). This work establishes the value of using single-layered films as heterogene ous catalysts and demonstrates the possibility of achieving high performance in CO2 reduction even with extremely low catalyst loadings.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 001177577200001 Publication Date 2024-02-28
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1614-6832; 1614-6840 ISBN Additional Links UA library record; WoS full record
  Impact Factor 27.8 Times cited Open Access
  Notes N.A. acknowledges a postdoctoral fellowship from the Research Foundation- Flanders (FWO) via grant 12ZS623N. S.D.F. acknowledges support from FWO (G0A4120N, G0H2122N, G0A5U24N), KU Leuven Internal Funds (grants C14/18/06, C14/19/079, C14/23/090), European Union under the Horizon Europe grant 101046231 (FantastiCOF), and M-ERA.NET via FWO (G0K9822N). S.D.F., K.M., Y.H., R.L., and S.V.A. were thankful to the FWO and FNRS for the financial support through the EOS program (grant 30489208, 40007495). Research in Mons was also supported by the Belgian National Fund for Scientific Research (FRS-FNRS) within the Consortium des Équipements de Calcul Intensif- CÉCI, and by the Walloon Region (ZENOBE and LUCIA Tier-1 supercomputers). E.J. appreciated the support from the Alexander von Humboldt Foundation, the Max Planck Society, the FLAG-ERA Grant OPERA by DFG 437130745, the National Natural Science Foundation of China (22288101), and the 111 Project (B17020). Partial financial support to M.R. from the Institut Universitaire de France (IUF) was warmly thanked. Approved Most recent IF: 27.8; 2024 IF: 16.721
  Call Number UA @ admin @ c:irua:204856 Serial 9172
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Author Ni, S.; Houwman, E.; Gauquelin, N.; Chezganov, D.; Van Aert, S.; Verbeeck, J.; Rijnders, G.; Koster, G.
  Title Stabilizing perovskite Pb(Mg0.33Nb0.67)O3-PbTiO3 thin films by fast deposition and tensile mismatched growth template Type A1 Journal article
  Year 2024 Publication ACS applied materials and interfaces Abbreviated Journal
  Volume 16 Issue 10 Pages 12744-12753
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Because of its low hysteresis, high dielectric constant, and strong piezoelectric response, Pb(Mg1/3Nb2/3)O-3-PbTiO3 (PMN-PT) thin films have attracted considerable attention for the application in PiezoMEMS, field-effect transistors, and energy harvesting and storage devices. However, it remains a great challenge to fabricate phase-pure, pyrochlore-free PMN-PT thin films. In this study, we demonstrate that a high deposition rate, combined with a tensile mismatched template layer can stabilize the perovskite phase of PMN-PT films and prevent the nucleation of passive pyrochlore phases. We observed that an accelerated deposition rate promoted mixing of the B-site cation and facilitated relaxation of the compressively strained PMN-PT on the SrTiO3 (STO) substrate in the initial growth layer, which apparently suppressed the initial formation of pyrochlore phases. By employing La-doped-BaSnO3 (LBSO) as the tensile mismatched buffer layer, 750 nm thick phase-pure perovskite PMN-PT films were synthesized. The resulting PMN-PT films exhibited excellent crystalline quality close to that of the STO substrate.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 001176343700001 Publication Date 2024-02-29
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1944-8244 ISBN Additional Links UA library record; WoS full record
  Impact Factor 9.5 Times cited Open Access
  Notes We would like to acknowledge the Netherlands Organization for Scientific Research (NWO) for the financial support of this work. This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No. 823717-ESTEEM3. Approved Most recent IF: 9.5; 2024 IF: 7.504
  Call Number UA @ admin @ c:irua:204754 Serial 9174
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Author Vandemeulebroucke, D.; Batuk, M.; Hajizadeh, A.; Wastiaux, M.; Roussel, P.; Hadermann, J.
  Title Incommensurate Modulations and Perovskite Growth in LaxSr2–xMnO4−δAffecting Solid Oxide Fuel Cell Conductivity Type A1 Journal Article
  Year 2024 Publication Chemistry of Materials Abbreviated Journal Chem. Mater.
  Volume Issue Pages
  Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
  Abstract Ruddlesden-Popper La????Sr2−????MnO4−???? materials are interesting symmetric solid oxide

fuel cell electrodes due to their good redox stability, mixed ionic and electronic conducting behavior and thermal expansion that matches well with common electrolytes. In reducing environments – as at a solid oxide fuel cell anode – the x = 0.5 member, i.e. La0.5Sr1.5MnO4−????, has a much higher total conductivity than compounds with a different La/Sr ratio, although all those compositions have the same K2NiF4-type I4/mmm structure. The origin for this conductivity difference is not yet known in literature. Now, a combination of in-situ and ex-situ 3D electron diffraction, high-resolution imaging, energy-dispersive X-ray analysis and electron energy-loss spectroscopy uncovered clear differences between x=0.25 and x=0.5 in the pristine structure, as well as in the transformations upon high-temperature reduction. In La0.5Sr1.5MnO4−????, Ruddlesden-Popper n=2 layer defects and an amorphous surface layer are present, but not in La0.25Sr1.75MnO4−????. After annealing at 700°C in 5% H2/Ar, La0.25Sr1.75MnO4−???? transforms to a tetragonal 2D incommensurately modulated structure with modulation vectors ⃗????1 = 0.2848(1) · (⃗????* +⃗????*) and ⃗????2 =0.2848(1) · (⃗????* – ⃗????*), whereas La0.5Sr1.5MnO4−???? only partially transforms to an orthorhombic 1D incommensurately modulated structure,

with ⃗???? = 0.318(2) · ⃗????*. Perovskite domains grow at the crystal edge at 700°C in 5%

H2 or vacuum, due to the higher La concentration on the surface compared to the bulk, which leads to a different thermodynamic equilibrium. Since it is known that a lower degree of oxygen vacancy ordering and a higher amount of perovskite blocks enhance oxygen mobility, those differences in defect structure and structural transformation upon reduction, might all contribute to the higher conductivity of La0.5Sr1.5MnO4−???? in solid oxide fuel cell anode conditions compared to other La/Sr ratios.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language English Wos (down) 001174840900001 Publication Date 2024-02-20
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record
  Impact Factor 8.6 Times cited Open Access Not_Open_Access
  Notes Universiteit Antwerpen, BOF TOP 38689 ; Fonds Wetenschappelijk Onderzoek, I003218N ; European Commission NanED, 956099 ; Approved Most recent IF: 8.6; 2024 IF: 9.466
  Call Number EMAT @ emat @c:irua:204354 Serial 8997
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Author Blagojević, J.; Mijin, S.D.; Bekaert, J.; Opačić, M.; Liu, Y.; Milošević, M.V.; Petrović, C.; Popović, Z.V.; Lazarević, N.
  Title Competition of disorder and electron-phonon coupling in 2H-TaSe2-xSx (0≤x≤2) as evidenced by Raman spectroscopy Type A1 Journal article
  Year 2024 Publication Physical review materials Abbreviated Journal
  Volume 8 Issue 2 Pages 024004-24008
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The vibrational properties of 2H-TaSe<sub>2-x</sub>S<sub>x</sub> (0≤x≤2) single crystals were probed using Raman spectroscopy and density functional theory calculations. The end members revealed two out of four symmetry-predicted Raman active modes, together with the pronounced two-phonon structure, attributable to the enhanced electron-phonon coupling. Additional peaks become observable due to crystallographic disorder for the doped samples. The evolution of the E<sub>2</sub>g<sup>2</sup> mode Fano parameter reveals that the disorder has a weak impact on electron-phonon coupling, which is also supported by the persistence of two-phonon structure in doped samples. As such, this research provides thorough insights into the lattice properties, the effects of crystallographic disorder on Raman spectra, and the interplay of this disorder with the electron-phonon coupling in 2H-TaSe<sub>2-x</sub>S<sub>x</sub> compounds.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos (down) 001171649400004 Publication Date 2024-02-21
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record
  Impact Factor 3.4 Times cited Open Access
  Notes Approved Most recent IF: 3.4; 2024 IF: NA
  Call Number UA @ admin @ c:irua:204404 Serial 9141
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