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Author |
Suslu, A.; Wu, K.; Sahin, H.; Chen, B.; Yang, S.; Cai, H.; Aoki, T.; Horzum, S.; Kang, J.; Peeters, F.M.; Tongay, S.; |
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Title |
Unusual dimensionality effects and surface charge density in 2D Mg(OH)2 |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
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Volume |
6 |
Issue |
6 |
Pages |
20525 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
We present two-dimensional Mg(OH)(2) sheets and their vertical heterojunctions with CVD-MoS2 for the first time as flexible 2D insulators with anomalous lattice vibration and chemical and physical properties. New hydrothermal crystal growth technique enabled isolation of environmentally stable monolayer Mg(OH)(2) sheets. Raman spectroscopy and vibrational calculations reveal that the lattice vibrations of Mg(OH)(2) have fundamentally different signature peaks and dimensionality effects compared to other 2D material systems known to date. Sub-wavelength electron energy-loss spectroscopy measurements and theoretical calculations show that Mg(OH)(2) is a 6 eV direct-gap insulator in 2D, and its optical band gap displays strong band renormalization effects from monolayer to bulk, marking the first experimental confirmation of confinement effects in 2D insulators. Interestingly, 2D-Mg(OH)(2) sheets possess rather strong surface polarization (charge) effects which is in contrast to electrically neutral h-BN materials. Using 2D-Mg(OH)(2) sheets together with CVD-MoS2 in the vertical stacking shows that a strong change transfer occurs from n-doped CVD-MoS2 sheets to Mg(OH)(2), naturally depleting the semiconductor, pushing towards intrinsic doping limit and enhancing overall optical performance of 2D semiconductors. Results not only establish unusual confinement effects in 2D-Mg(OH)(2), but also offer novel 2D-insulating material with unique physical, vibrational, and chemical properties for potential applications in flexible optoelectronics. |
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Thesis |
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Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
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Language |
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Wos |
000369510300001 |
Publication Date |
2016-02-05 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2045-2322 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.259 |
Times cited |
39 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). HS is supported by a FWO Pegasus Long Marie Curie Fellowship. JK is supported by a FWO Pegasus-short Marie Curie Fellowship. We acknowledge the use of John M. Cowley Center for High Resolution Electron Microscopy at Arizona State University. ; |
Approved |
Most recent IF: 4.259 |
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Call Number |
UA @ lucian @ c:irua:131615 |
Serial |
4272 |
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Permanent link to this record |
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Author |
Yagmurcukardes, M.; Peeters, F.M.; Senger, R.T.; Sahin, H. |
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Title |
Nanoribbons: From fundamentals to state-of-the-art applications |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Applied physics reviews |
Abbreviated Journal |
Appl Phys Rev |
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Volume |
3 |
Issue |
3 |
Pages |
041302 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Atomically thin nanoribbons (NRs) have been at the forefront of materials science and nanoelectronics in recent years. State-of-the-art research on nanoscale materials has revealed that electronic, magnetic, phononic, and optical properties may differ dramatically when their one-dimensional forms are synthesized. The present article aims to review the recent advances in synthesis techniques and theoretical studies on NRs. The structure of the review is organized as follows: After a brief introduction to low dimensional materials, we review different experimental techniques for the synthesis of graphene nanoribbons (GNRs) with their advantages and disadvantages. In addition, theoretical investigations on width and edge-shape-dependent electronic and magnetic properties, functionalization effects, and quantum transport properties of GNRs are reviewed. We then devote time to the NRs of the transition metal dichalcogenides (TMDs) family. First, various synthesis techniques, E-field-tunable electronic and magnetic properties, and edge-dependent thermoelectric performance of NRs of MoS2 and WS2 are discussed. Then, strongly anisotropic properties, growth-dependent morphology, and the weakly width-dependent bandgap of ReS2 NRs are summarized. Next we discuss TMDs having a T-phase morphology such as TiSe2 and stable single layer NRs of mono-chalcogenides. Strong edge-type dependence on characteristics of GaS NRs, width-dependent Seebeck coefficient of SnSe NRs, and experimental analysis on the stability of ZnSe NRs are reviewed. We then focus on the most recently emerging NRs belonging to the class of transition metal trichalcogenides which provide ultra-high electron mobility and highly anisotropic quasi-1D properties. In addition, width-, edge-shape-, and functionalization-dependent electronic and mechanical properties of blackphosphorus, a monoatomic anisotropic material, and studies on NRs of group IV elements (silicene, germanene, and stanene) are reviewed. Observation of substrate-independent quantum well states, edge and width dependent properties, the topological phase of silicene NRs are reviewed. In addition, H-2 concentration-dependent transport properties and anisotropic dielectric function of GeNRs and electric field and strain sensitive I-V characteristics of SnNRs are reviewed. We review both experimental and theoretical studies on the NRs of group III-V compounds. While defect and N-termination dependent conductance are highlighted for boron nitride NRs, aluminum nitride NRs are of importance due to their dangling bond, electric field, and strain dependent electronic and magnetic properties. Finally, superlattice structure of NRs of GaN/AlN, Si/Ge, G/BN, and MoS2/WS2 is reviewed. Published by AIP Publishing. |
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Corporate Author |
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Thesis |
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Publisher |
Amer inst physics |
Place of Publication |
Melville |
Editor |
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Language |
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Wos |
000390443800013 |
Publication Date |
2016-11-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1931-9401 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.667 |
Times cited |
63 |
Open Access |
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Notes |
; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges the support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP program. R.T.S. acknowledges the support from TUBITAK through Project No. 114F397. F.M.P. was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program. ; |
Approved |
Most recent IF: 13.667 |
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Call Number |
UA @ lucian @ c:irua:140299 |
Serial |
4457 |
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Permanent link to this record |
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Author |
Yagmurcukardes, M.; Bacaksiz, C.; Unsal, E.; Akbali, B.; Senger, R.T.; Sahin, H. |
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Title |
Strain mapping in single-layer two-dimensional crystals via Raman activity |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
97 |
Issue |
11 |
Pages |
115427 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
By performing density functional theory-based ab initio calculations, Raman-active phonon modes of single-layer two-dimensional (2D) materials and the effect of in-plane biaxial strain on the peak frequencies and corresponding activities of the Raman-active modes are calculated. Our findings confirm the Raman spectrum of the unstrained 2D crystals and provide expected variations in the Raman-active modes of the crystals under in-plane biaxial strain. The results are summarized as follows: (i) frequencies of the phonon modes soften (harden) under applied tensile (compressive) strains; (ii) the response of the Raman activities to applied strain for the in-plane and out-of-plane vibrational modes have opposite trends, thus, the built-in strains in the materials can be monitored by tracking the relative activities of those modes; (iii) in particular, the A peak in single-layer Si and Ge disappears under a critical tensile strain; (iv) especially in mono-and diatomic single layers, the shift of the peak frequencies is a stronger indication of the strain rather than the change in Raman activities; (v) Raman-active modes of single-layer ReX2 (X = S, Se) are almost irresponsive to the applied strain. Strain-induced modifications in the Raman spectrum of 2D materials in terms of the peak positions and the relative Raman activities of the modes could be a convenient tool for characterization. |
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Corporate Author |
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Thesis |
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Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
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Language |
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Wos |
000427799300006 |
Publication Date |
2018-03-19 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
21 |
Open Access |
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Notes |
; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 116C073. ; |
Approved |
Most recent IF: 3.836 |
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Call Number |
UA @ lucian @ c:irua:150840UA @ admin @ c:irua:150840 |
Serial |
4979 |
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Permanent link to this record |
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Author |
Yagmurcukardes, M.; Peeters, F.M.; Sahin, H. |
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Title |
Electronic and vibrational properties of PbI2: From bulk to monolayer |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
98 |
Issue |
8 |
Pages |
085431 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Using first-principles calculations, we study the dependence of the electronic and vibrational properties of multilayered PbI2 crystals on the number of layers and focus on the electronic-band structure and the Raman spectrum. Electronic-band structure calculations reveal that the direct or indirect semiconducting behavior of PbI2 is strongly influenced by the number of layers. We find that at 3L thickness there is a direct-to-indirect band gap transition (from bulk-to-monolayer). It is shown that in the Raman spectrum two prominent peaks, A(1g) and E-g, exhibit phonon hardening with an increasing number of layers due to the interlayer van der Waals interaction. Moreover, the Raman activity of the A(1g) mode significantly increases with an increasing number of layers due to the enhanced out-of-plane dielectric constant in the few-layer case. We further characterize rigid-layer vibrations of low-frequency interlayer shear (C) and breathing (LB) modes in few-layer PbI2. A reduced monatomic (linear) chain model (LCM) provides a fairly accurate picture of the number of layers dependence of the low-frequency modes and it is shown also to be a powerful tool to study the interlayer coupling strength in layered PbI2. |
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Corporate Author |
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Thesis |
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Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
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Language |
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Wos |
000442667200008 |
Publication Date |
2018-08-24 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
41 |
Open Access |
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Notes |
; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 117F095. Part of this work was supported by FLAG-ERA project TRANS-2D-TMD. ; |
Approved |
Most recent IF: 3.836 |
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Call Number |
UA @ lucian @ c:irua:153716UA @ admin @ c:irua:153716 |
Serial |
5097 |
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Permanent link to this record |
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Author |
Torun, E.; Sahin, H.; Chaves, A.; Wirtz, L.; Peeters, F.M. |
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Title |
Ab initio and semiempirical modeling of excitons and trions in monolayer TiS3 |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
98 |
Issue |
7 |
Pages |
075419 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
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Language |
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Wos |
000442342100002 |
Publication Date |
2018-08-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
10 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the FLAG-ERA project TRANS-2D-TMD. H.S. acknowledges financial support from TUBITAK under Project No. 117F095. A.C. acknowledges support from the Brazilian Research Council (CNPq), through the PRONEX/FUNCAP and Science Without Borders programs, and from the Lemann Foundation. E.T. and L.W. acknowledge support from the National Research Fund, Luxembourg (IN-TER/ANR/13/20/NANOTMD). ; |
Approved |
Most recent IF: 3.836 |
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Call Number |
UA @ lucian @ c:irua:153721UA @ admin @ c:irua:153721 |
Serial |
5076 |
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Permanent link to this record |
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Author |
Sen, H.S.; Sahin, H.; Peeters, F.M.; Durgun, E. |
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Title |
Monolayers of MoS2 as an oxidation protective nanocoating material |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
116 |
Issue |
8 |
Pages |
083508 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
First-principle calculations are employed to investigate the interaction of oxygen with ideal and defective MoS2 monolayers. Our calculations show that while oxygen atoms are strongly bound on top of sulfur atoms, the oxygen molecule only weakly interacts with the surface. The penetration of oxygen atoms and molecules through a defect-free MoS2 monolayer is prevented by a very high diffusion barrier indicating that MoS2 can serve as a protective layer for oxidation. The analysis is extended to WS2 and similar coating characteristics are obtained. Our calculations indicate that ideal and continuous MoS2 and WS2 monolayers can improve the oxidation and corrosion-resistance of the covered surface and can be considered as an efficient nanocoating material. (C) 2014 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000342821600017 |
Publication Date |
2014-08-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979;1089-7550; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.068 |
Times cited |
52 |
Open Access |
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Notes |
; This work was supported by the bilateral project between TUBITAK (through Grant No. 113T050) and Flemish Science Foundation (FWO-Vl). The calculations were performed at TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). E.D. acknowledges support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP program. H.S. is supported by an FWO Pegasus-long Marie Curie Fellowship. ; |
Approved |
Most recent IF: 2.068; 2014 IF: 2.183 |
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Call Number |
UA @ lucian @ c:irua:121101 |
Serial |
2194 |
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Permanent link to this record |
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Author |
Torun, E.; Sahin, H.; Singh, S.K.; Peeters, F.M. |
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Title |
Stable half-metallic monolayers of FeCl2 |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
106 |
Issue |
106 |
Pages |
192404 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The structural, electronic, and magnetic properties of single layers of Iron Dichloride (FeCl2) were calculated using first principles calculations. We found that the 1T phase of the single layer FeCl2 is 0.17 eV/unit cell more favorable than its 1H phase. The structural stability is confirmed by phonon calculations. We found that 1T-FeCl2 possess three Raman-active (130, 179, and 237 cm(-1)) and one infrared-active (279 cm(-1)) phonon branches. The electronic band dispersion of the 1T-FeCl2 is calculated using both gradient approximation of Perdew-Burke-Ernzerhof and DFT-HSE06 functionals. Both functionals reveal that the 1T-FeCl2 has a half-metallic ground state with a Curie temperature of 17 K. (C) 2015 AIP Publishing LLC. |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000355008100020 |
Publication Date |
2015-05-13 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-6951;1077-3118; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.411 |
Times cited |
84 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. was supported by a FWO Pegasus Long Marie Curie Fellowship. ; |
Approved |
Most recent IF: 3.411; 2015 IF: 3.302 |
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Call Number |
c:irua:126411 |
Serial |
3143 |
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Permanent link to this record |
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Author |
Yagmurcukardes, M.; Sahin, H.; Kang, J.; Torun, E.; Peeters, F.M.; Senger, R.T. |
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Title |
Pentagonal monolayer crystals of carbon, boron nitride, and silver azide |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
118 |
Issue |
118 |
Pages |
104303 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
In this study, we present a theoretical investigation of structural, electronic, and mechanical properties of pentagonal monolayers of carbon (p-graphene), boron nitride (p-B2N4 and p-B4N2), and silver azide (p-AgN3) by performing state-of-the-art first principles calculations. Our total energy calculations suggest feasible formation of monolayer crystal structures composed entirely of pentagons. In addition, electronic band dispersion calculations indicate that while p-graphene and p-AgN3 are semiconductors with indirect bandgaps, p-BN structures display metallic behavior. We also investigate the mechanical properties (in-plane stiffness and the Poisson's ratio) of four different pentagonal structures under uniaxial strain. p-graphene is found to have the highest stiffness value and the corresponding Poisson's ratio is found to be negative. Similarly, p-B2N4 and p-B4N2 have negative Poisson's ratio values. On the other hand, the p-AgN3 has a large and positive Poisson's ratio. In dynamical stability tests based on calculated phonon spectra of these pentagonal monolayers, we find that only p-graphene and p-B2N4 are stable, but p-AgN3 and p-B4N2 are vulnerable against vibrational excitations. |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000361636900028 |
Publication Date |
2015-09-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979; 1089-7550 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.068 |
Times cited |
79 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. was supported by a FWO Pegasus Long Marie Curie Fellowship. H.S. and R.T.S. acknowledge the support from TUBITAK through Project No. 114F397. ; |
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
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Call Number |
UA @ lucian @ c:irua:128415 |
Serial |
4223 |
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Permanent link to this record |
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Author |
Torun, E.; Sahin, H.; Cahangirov, S.; Rubio, A.; Peeters, F.M. |
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Title |
Anisotropic electronic, mechanical, and optical properties of monolayer WTe2 |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
119 |
Issue |
7 |
Pages |
074307 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Using first-principles calculations, we investigate the electronic, mechanical, and optical properties of monolayer WTe2. Atomic structure and ground state properties of monolayer WTe2 (T-d phase) are anisotropic which are in contrast to similar monolayer crystals of transition metal dichalcogenides, such as MoS2, WS2, MoSe2, WSe2, and MoTe2, which crystallize in the H-phase. We find that the Poisson ratio and the in-plane stiffness is direction dependent due to the symmetry breaking induced by the dimerization of the W atoms along one of the lattice directions of the compound. Since the semimetallic behavior of the T-d phase originates from this W-W interaction (along the a crystallographic direction), tensile strain along the dimer direction leads to a semimetal to semiconductor transition after 1% strain. By solving the Bethe-Salpeter equation on top of single shot G(0)W(0) calculations, we predict that the absorption spectrum of T-d-WTe2 monolayer is strongly direction dependent and tunable by tensile strain. (C) 2016 AIP Publishing LLC. |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000375158000022 |
Publication Date |
2016-02-19 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979; 1089-7550 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.068 |
Times cited |
62 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-V1) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. was supported by a FWO Pegasus Long Marie Curie Fellowship. S.C. and A.R. acknowledge the financial support from the Marie Curie grant FP7-PEOPLE-2013-IEF Project No. 628876, European Research Council (ERC-2010-AdG-267374), Spanish grant (FIS2013-46159-C3-1-P), Grupos Consolidados (IT578-13), and AFOSR Grant No. FA2386-15-1-0006 AOARD 144088, H2020-NMP-2014 project MOSTOPHOS, GA No. SEP-210187476, and COST Action MP1306 (EUSpec). S.C. acknowledges the support from The Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 115F388. ; |
Approved |
Most recent IF: 2.068 |
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Call Number |
UA @ lucian @ c:irua:144747 |
Serial |
4640 |
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Permanent link to this record |
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Author |
Kandemir, A.; Peeters, F.M.; Sahin, H. |
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Title |
Monitoring the effect of asymmetrical vertical strain on Janus single layers of MoSSe via spectrum |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
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Volume |
149 |
Issue |
8 |
Pages |
084707 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Using first principles calculations, we study the structural and phononic properties of the recently synthesized Janus type single layers of molybdenum dichalcogenides. The Janus MoSSe single layer possesses 2H crystal structure with two different chalcogenide sides that lead to out-of-plane anisotropy. By virtue of the asymmetric structure of the ultra-thin Janus type crystal, we induced the out-of-plane anisotropy to show the distinctive vertical pressure effect on the vibrational properties of the Janus material. It is proposed that for the corresponding Raman active optical mode of the Janus structure, the phase modulation and the magnitude ratio of the strained atom and its first neighbor atom adjust the distinctive change in the eigen-frequencies and Raman activity. Moreover, a strong variation in the Raman activity of the Janus structure is obtained under bivertical and univertical strains. Not only eigen-frequency shifts but also Raman activities of the optical modes of the Janus structure exhibit distinguishable features. This study reveals that the vertical anisotropic feature of the Janus structure under Raman measurement allows us to distinguish which side of the Janus crystal interacts with the externals (substrate, functional adlayers, or dopants). Published by AIP Publishing. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000444035800044 |
Publication Date |
2018-08-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-9606 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.965 |
Times cited |
11 |
Open Access |
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Notes |
; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges financial support from TUBITAK under Project No. 117F095. F.M.P. was supported by the FLAG-ERA-TRANS<INF>2D</INF>TMD. ; |
Approved |
Most recent IF: 2.965 |
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Call Number |
UA @ lucian @ c:irua:153711UA @ admin @ c:irua:153711 |
Serial |
5115 |
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Permanent link to this record |
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Author |
Yang, S.; Wang, C.; Sahin, H.; Chen, H.; Li, Y.; Li, S.S.; Suslu, A.; Peeters, F.M.; Liu, Q.; Li, J.; Tongay, S.; |
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Title |
Tuning the optical, magnetic, and electrical properties of ReSe2 by nanoscale strain engineering |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
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Volume |
15 |
Issue |
15 |
Pages |
1660-1666 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Creating materials with ultimate control over their physical properties is vital for a wide range of applications. From a traditional materials design perspective, this task often requires precise control over the atomic composition and structure. However, owing to their mechanical properties, low-dimensional layered materials can actually withstand a significant amount of strain and thus sustain elastic deformations before fracture. This, in return, presents a unique technique for tuning their physical properties by strain engineering. Here, we find that local strain induced on ReSe2, a new member of the transition metal dichalcogenides family, greatly changes its magnetic, optical, and electrical properties. Local strain induced by generation of wrinkle (1) modulates the optical gap as evidenced by red-shifted photoluminescence peak, (2) enhances light emission, (3) induces magnetism, and (4) modulates the electrical properties. The results not only allow us to create materials with vastly different properties at the nanoscale, but also enable a wide range of applications based on 2D materials, including strain sensors, stretchable electrodes, flexible field-effect transistors, artificial-muscle actuators, solar cells, and other spintronic, electromechanical, piezoelectric, photonic devices. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington |
Editor |
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Language |
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Wos |
000351188000033 |
Publication Date |
2015-02-02 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1530-6984;1530-6992; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.712 |
Times cited |
314 |
Open Access |
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Notes |
; This work is supported by Arizona State University, Research Seeding Program, the National Natural Science Foundation of China (91233120), and the National Basic Research Program of China (2011CB921901). Q., Liu acknowledges the support to this work by NSFC (10974037), NBRPC (2010CB934102), and the CAS Strategy Pilot program (XDA 09020300). S. Yang acknowledges financial support from China Postdoctoral Science Foundation (No. 2013M540127). ; |
Approved |
Most recent IF: 12.712; 2015 IF: 13.592 |
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Call Number |
c:irua:125480 |
Serial |
3758 |
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Permanent link to this record |
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Author |
Esfahani; Leenaerts, O.; Sahin, H.; Partoens, B.; Peeters, F.M. |
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Title |
Structural transitions in monolayer MOS2 by lithium adsorption |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
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Volume |
119 |
Issue |
119 |
Pages |
10602-10609 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Based on first-principles calculations, we study the structural stability of the H and T phases of monolayer MoS2 upon Li doping. Our calculations demonstrate that it is possible to stabilize a distorted T phase of MoS2 over the H phase through adsorption of Li atoms on the MoS2 surface. Through molecular dynamics and phonon calculations, we show that the T phase of MoS2 is dynamically unstable and undergoes considerable distortions. The type of distortion depends on the concentration of adsorbed Li atoms and changes from zigzag-like to diamond-like when increasing the Li doping. There exists a substantial energy barrier to transform the stable H phase to the distorted T phases, which is considerably reduced by increasing the concentration of Li atoms. We show that it is necessary that the Li atoms adsorb on both sides of the MoS2 monolayer to reduce the barrier sufficiently. Two processes are examined that allow for such two-sided adsorption, namely, penetration through the MoS2 layer and diffusion over the MoS2 surface. We show that while there is only a small barrier of 0.24 eV for surface diffusion, the amount of energy needed to pass through a pure MoS2 layer is of the order of similar or equal to 2 eV. However, when the MoS2 layer is covered with Li atoms the amount of energy that Li atoms should gain to penetrate the layer is drastically reduced and penetration becomes feasible. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000354912200051 |
Publication Date |
2015-04-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1932-7447;1932-7455; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.536 |
Times cited |
96 |
Open Access |
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Notes |
; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl) and the Methusalem program of the Flemish government. H. S is supported by an FWO Pegasus-Long Marie Curie fellowship. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government department EWI. ; |
Approved |
Most recent IF: 4.536; 2015 IF: 4.772 |
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Call Number |
c:irua:126409 |
Serial |
3270 |
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Permanent link to this record |
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Author |
Kang, J.; Sahin, H.; Peeters, F.M. |
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Title |
Tuning carrier confinement in the MoS2/WS2 lateral heterostructure |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
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Volume |
119 |
Issue |
119 |
Pages |
9580-9586 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
To determine and control the spatial confinement of charge carriers is of importance for nanoscale optoelectronic device applications. Using first-principles calculations, we investigate the tunability of band alignment and Charge localization in lateral and combined lateral vertical heterostructures of MoS2 and WS2. First, we Show that a type-II to type-I band alignment transition takes place when tensile strain is applied on the WS2 region. This band alignment transition is a result of the different response of the band edge states with strain and is caused by their different wave function characters. Then we show that the presence of the grain boundary introduces localized in-gap states. The boundary at the armchair interface significantly modifies the charge distribution of the valence band maximum (VBM) state, whereas in a heterostructure with tilt grain domains both conducation band maximum (CBM) and VBM are found to be localized around the grain boundary. We also found that the thickness of the constituents in a lateral heterostructure also determines how the electrons and holes are confined. Creating combined lateral vertical heterostructures of MOS2/WS2 provides another way cif tuning the charge confinement. These results provide possible ways to tune the carrier confinement in MoS2/WS2 heterostructures, which are interesting for its practical: applications in the future. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000353930700066 |
Publication Date |
2015-04-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1932-7447;1932-7455; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.536 |
Times cited |
73 |
Open Access |
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Notes |
; This work was supported by the Methusalem program of the Flemish government. H.S. is supported by a FWO Pegasus Marie Curie-long Fellowship and J.K. by a FWO Pegasus Marie Curie-short Fellowship. ; |
Approved |
Most recent IF: 4.536; 2015 IF: 4.772 |
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Call Number |
c:irua:126381 |
Serial |
3747 |
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Permanent link to this record |
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Author |
Iyikanat, F.; Sahin, H.; Senger, R.T.; Peeters, F.M. |
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Title |
Vacancy formation and oxidation characteristics of single layer TiS3 |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
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Volume |
119 |
Issue |
119 |
Pages |
10709-10715 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
The structural, electronic, and magnetic properties of pristine, defective, and oxidized monolayer TiS3 are investigated using first-principles calculations in the framework of density functional theory. We found that a single layer of TiS3 is a direct band gap semiconductor, and the bonding nature of the crystal is fundamentally different from other transition metal chalcogenides. The negatively charged surfaces of single layer TiS3 makes this crystal a promising material for lubrication applications. The formation energies of possible vacancies, i.e. S, Ti, TiS, and double S, are investigated via total energy optimization calculations. We found that the formation of a single S vacancy was the most likely one among the considered vacancy types. While a single S vacancy results in a nonmagnetic, semiconducting character with an enhanced band gap, other vacancy types induce metallic behavior with spin polarization of 0.3-0.8 mu(B). The reactivity of pristine and defective TiS3 crystals against oxidation was investigated using conjugate gradient calculations where we considered the interaction with atomic O, O-2, and O-3. While O-2 has the lowest binding energy with 0.05-0.07 eV, O-3 forms strong bonds stable even at moderate temperatures. The strong interaction (3.9-4.0 eV) between atomic O and TiS3 results in dissociative adsorption of some O-containing molecules. In addition, the presence of S-vacancies enhances the reactivity of the surface with atomic O, whereas it had a negative effect on the reactivity with O-2 and O-3 molecules. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000354912200063 |
Publication Date |
2015-04-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1932-7447;1932-7455; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.536 |
Times cited |
51 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. H.S. is supported by a FWO Pegasus Marie Curie Fellowship. RI., H.S., and R.T.S. acknowledge the support from TUBITAK through project 114F397. ; |
Approved |
Most recent IF: 4.536; 2015 IF: 4.772 |
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Call Number |
c:irua:126410 |
Serial |
3829 |
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Permanent link to this record |
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Author |
Iyikanat, F.; Senger, R.T.; Peeters, F.M.; Sahin, H. |
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Title |
Quantum-Transport Characteristics of a p-n Junction on Single-Layer TiS3 |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
ChemPhysChem : a European journal of chemical physics and physical chemistry |
Abbreviated Journal |
Chemphyschem |
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Volume |
17 |
Issue |
17 |
Pages |
3985-3991 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
By using density functional theory and non-equilibrium Green's function-based methods, we investigated the electronic and transport properties of a TiS3 monolayer p-n junction. We constructed a lateral p-n junction on a TiS3 monolayer using Li and F adatoms. An applied bias voltage caused significant variability in the electronic and transport properties of the TiS3 p-n junction. In addition, the spin-dependent current-volt-age characteristics of the constructed TiS3 p-n junction were analyzed. Important device characteristics were found, such as negative differential resistance and rectifying diode behaviors for spin-polarized currents in the TiS3 p-n junction. These prominent conduction properties of the TiS3 p-n junction offer remarkable opportunities for the design of nanoelectronic devices based on a recently synthesized single-layered material. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
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Language |
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Wos |
000389534800018 |
Publication Date |
2016-09-29 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1439-4235 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.075 |
Times cited |
12 |
Open Access |
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Notes |
; This work was supported by the bilateral project between TUBITAK (through Grant No. 113T050) and the Flemish Science Foundation (FWO-Vl). The calculations were performed at TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). FI, HS, and RTS acknowledge the support from TUBITAK Project No 114F397. H.S. acknowledges support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP program. ; |
Approved |
Most recent IF: 3.075 |
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Call Number |
UA @ lucian @ c:irua:140245 |
Serial |
4458 |
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Permanent link to this record |