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Author (up) Bafekry, A.; Ghergherehchi, M.; Shayesteh, S.F.; Peeters, F.M. pdf  doi
openurl 
  Title Adsorption of molecules on C3N nanosheet : a first-principles calculations Type A1 Journal article
  Year 2019 Publication Chemical physics Abbreviated Journal Chem Phys  
  Volume 526 Issue 526 Pages 110442  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using first-principles calculations we investigate the interaction of various molecules, including H-2, N-2, CO, CO2, H2O, H2S, NH3, CH4 with a C3N nanosheet. Due to the weaker interaction between H-2, N-2, CO, CO2, H2O, H2S, NH3, and CH4 molecules with C3N, the adsorption energy is small and does not yield any significant distortion of the C3N lattice and the molecules are physisorbed. Calculated charge transfer shows that these molecules act as weak donors. However, adsorption of O-2, NO, NO2 and SO2 molecules are chemisorbed, they receive electrons from C3N and act as a strong acceptor. They interact strongly through hybridizing its frontier orbitals with the p-orbital of C3N, modifying the electronic structure of C3N. Our theoretical studies indicate that C3N-based sensor has a high potential for O-2, NO, NO2 and SO2 molecules detection.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000481606000006 Publication Date 2019-07-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0301-0104 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.767 Times cited 46 Open Access  
  Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). In addition, this work was supported by the FLAG-ERA project 2DTRANS and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 1.767  
  Call Number UA @ admin @ c:irua:161779 Serial 5405  
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Author (up) Bafekry, A.; Gogova, D.; M. Fadlallah, M.; V. Chuong, N.; Ghergherehchi, M.; Faraji, M.; Feghhi, S.A.H.; Oskoeian, M. url  doi
openurl 
  Title Electronic and optical properties of two-dimensional heterostructures and heterojunctions between doped-graphene and C- and N-containing materials Type A1 Journal article
  Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 23 Issue 8 Pages 4865-4873  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The electronic and optical properties of vertical heterostructures (HTSs) and lateral heterojunctions (HTJs) between (B,N)-codoped graphene (dop@Gr) and graphene (Gr), C3N, BC3 and h-BN monolayers are investigated using van der Waals density functional theory calculations. We have found that all the considered HTSs are energetically and thermally feasible at room temperature, and therefore they can be synthesized experimentally. The dop@Gr/Gr, BC3/dop@Gr and BN/dop@Gr HTSs are semiconductors with direct bandgaps of 0.1 eV, 80 meV and 1.23 eV, respectively, while the C3N/dop@Gr is a metal because of the strong interaction between dop@Gr and C3N layers. On the other hand, the dop@Gr-Gr and BN-dop@Gr HTJs are semiconductors, whereas the C3N-dop@Gr and BC3-dop@Gr HTJs are metals. The proposed HTSs can enhance the absorption of light in the whole wavelength range as compared to Gr and BN monolayers. The applied electric field or pressure strain changes the bandgaps of the HTSs and HTJs, indicating that these HTSs are highly promising for application in nanoscale multifunctional devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000625306100038 Publication Date 2021-02-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.123 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:177659 Serial 6986  
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Author (up) Bafekry, A.; Karbasizadeh, S.; Stampfl, C.; Faraji, M.; Hoat, D.M.; Sarsari, I.A.; Feghhi, S.A.H.; Ghergherehchi, M. url  doi
openurl 
  Title Two-dimensional Janus semiconductor BiTeCl and BiTeBr monolayers : a first-principles study on their tunable electronic properties via an electric field and mechanical strain Type A1 Journal article
  Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 23 Issue 28 Pages 15216-15223  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Motivated by the recent successful synthesis of highly crystalline ultrathin BiTeCl and BiTeBr layered sheets [Debarati Hajra et al., ACS Nano, 2020, 14, 15626], herein for the first time, we carry out a comprehensive study on the structural and electronic properties of BiTeCl and BiTeBr Janus monolayers using density functional theory (DFT) calculations. Different structural and electronic parameters including the lattice constant, bond lengths, layer thickness in the z-direction, different interatomic angles, work function, charge density difference, cohesive energy and Rashba coefficients are determined to acquire a deep understanding of these monolayers. The calculations show good stability of the studied single layers. BiTeCl and BiTeBr monolayers are semiconductors with electronic bandgaps of 0.83 and 0.80 eV, respectively. The results also show that the semiconductor-metal transformation can be induced by increasing the number of layers. In addition, the engineering of the electronic structure is also studied by applying an electric field, and mechanical uniaxial and biaxial strain. The results show a significant change of the bandgaps and that an indirect-direct band-gap transition can be induced. This study highlights the positive prospect for the application of BiTeCl and BiTeBr layered sheets in novel electronic and energy conversion systems.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000670553900001 Publication Date 2021-06-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.123 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:179827 Serial 7042  
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Author (up) Bafekry, A.; Mortazavi, B.; Faraji, M.; Shahrokhi, M.; Shafique, A.; Jappor, H.R.; Nguyen, C.; Ghergherehchi, M.; Feghhi, S.A.H. url  doi
openurl 
  Title Ab initio prediction of semiconductivity in a novel two-dimensional Sb₂X₃ (X= S, Se, Te) monolayers with orthorhombic structure Type A1 Journal article
  Year 2021 Publication Scientific Reports Abbreviated Journal Sci Rep-Uk  
  Volume 11 Issue 1 Pages 10366  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Sb2S3 and Sb2Se3 are well-known layered bulk structures with weak van der Waals interactions. In this work we explore the atomic lattice, dynamical stability, electronic and optical properties of Sb2S3, Sb2Se3 and Sb2Te3 monolayers using the density functional theory simulations. Molecular dynamics and phonon dispersion results show the desirable thermal and dynamical stability of studied nanosheets. On the basis of HSE06 and PBE/GGA functionals, we show that all the considered novel monolayers are semiconductors. Using the HSE06 functional the electronic bandgap of Sb2S3, Sb2Se3 and Sb2Te3 monolayers are predicted to be 2.15, 1.35 and 1.37 eV, respectively. Optical simulations show that the first absorption coefficient peak for Sb2S3, Sb2Se3 and Sb2Te3 monolayers along in-plane polarization is suitable for the absorption of the visible and IR range of light. Interestingly, optically anisotropic character along planar directions can be desirable for polarization-sensitive photodetectors. Furthermore, we systematically investigate the electrical transport properties with combined first-principles and Boltzmann transport theory calculations. At optimal doping concentration, we found the considerable larger power factor values of 2.69, 4.91, and 5.45 for hole-doped Sb2S3, Sb2Se3, and Sb2Te3, respectively. This study highlights the bright prospect for the application of Sb2S3, Sb2Se3 and Sb2Te3 nanosheets in novel electronic, optical and energy conversion systems.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000656961400019 Publication Date 2021-05-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.259 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 4.259  
  Call Number UA @ admin @ c:irua:179188 Serial 6965  
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Author (up) Bafekry, A.; Mortazavic, B.; Shayesteh, S.F. pdf  doi
openurl 
  Title Band gap and magnetism engineering in Dirac half-metallic Na2C nanosheet via layer thickness, strain and point defects Type A1 Journal article
  Year 2019 Publication Journal of magnetism and magnetic materials Abbreviated Journal J Magn Magn Mater  
  Volume 491 Issue 491 Pages 165565  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Na2C is a novel two-dimensional material with Dirac Half-metal (DHM) characteristic, exhibiting a combination of single-spin massless Dirac fermions and half-semimetal. In this paper based on the first-principles calculations, we studied the mechanical, electronic, magnetic and optical properties of Na2C nanosheet. The elastic modulus of Na2C was measured to 18.5 N/m and isotropic, whereas it shows anisotropic tensile strengths of 2.85 and 2.04 N/m, for the loading along the zigzag and armchair directions, respectively. We found that Na2C, is a DHM with band gap of 0.7 eV in the up-spin channel and has 2 mu(B) magnetic moment per unit cell. In addition, we investigated the effects of number of atomic layers (thickness), electric field and strain on the possibility of further tuning of the electronic and magnetic properties of Na2C. Our calculations show that by increasing the number of layers from monolayer to bulk, a transition from DHM to ferromagnetic metal occurs with a high magnetic moments in the range of 16-30 mu(B). With applying an electric field on the Na2C bilayer (within the ferromagnetic and anti-ferromagnetic orders), energy band gap is slightly increased. In addition our results indicate that the electronic structure can be significantly modified by applying the mechanical straining. In this regard, under the biaxial strain (from 0% to – 8%) or large uniaxial strains (> – 6%), we observed the DHM to ferromagnetic-metal transition. Moreover, vacancy defects and atom substitutions can also effect the electronic and magnetic properties of Na2C nanosheet. Defective Na2C with single and double vacancies, was found to show the metallic response. With various atom substitutions this nanosheet exhibits; ferromagnetic-metal (Si and Be) with 5.2 and 3 mu(B); dilute-magnetic semiconductor (B and N) with 3 and 7 mu(B) magnetic moments, respectively. In the case of B or N atoms replacing the native C atom, the down-spin channel yields about 1 eV band gap. Interestingly, replacing the Na atoms in the native Na2C lattice with the Li can result in the formation of magnetic topological insulator phase with nontrivial band gap in the down-spin channel (25 meV and 0.15 eV) and up-spin channel (0.75 eV), in addition exhibit 8 mu(B) magnetic moment in the ground state.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000486396100010 Publication Date 2019-07-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-8853 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.63 Times cited 13 Open Access  
  Notes ; B. M. appreciates the funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germanys Excellence Strategy within the Cluster of Excellence PhoenixD (EXC 2122, Project ID 390833453). We acknowledge OpenMX team for OpenMX code. ; Approved Most recent IF: 2.63  
  Call Number UA @ admin @ c:irua:163697 Serial 5408  
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Author (up) Bafekry, A.; Neek-Amal, M. url  doi
openurl 
  Title Tuning the electronic properties of graphene-graphitic carbon nitride heterostructures and heterojunctions by using an electric field Type A1 Journal article
  Year 2020 Publication Physical Review B Abbreviated Journal Phys Rev B  
  Volume 101 Issue 8 Pages 085417-10  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Integration of graphene-based two-dimensional materials is essential for nanoelectronics applications. Using density-functional theory, we systematically investigate the electronic properties of vertically stacked graphene-graphitic carbon nitrides (GE/GCN). We also studied the covalently lateral stitched graphene-graphitic carbon nitrides (GE-GCN heterojunctions). The effects of perpendicular electric field on the electronic properties of six different heterostructures, i.e., (i) one layer of GE on top of a layer of CnNm with (n, m) = (3,1), (3,4), and (4,3) and (ii) three heterostructures CnNm/Cn'Nm', where (n, m) not equal (n', m') are elucidated. The most important calculated features are (i) the systems GE/C3N4, C3N/C3N4, GE-C3N, GE-C4N3, and C3N-C3N4 exhibit semiconducting characteristics having small band gaps of Delta(0)=20, 250, 100, 100, 80 meV, respectively while (ii) the systems GE/C4N3, C3N/C4N3, and C3N-C4N3 show ferromagnetic-metallic properties. In particular, we found that, in semiconducting heterostructures, the band gap increases nontrivially with increasing the absolute value of the applied perpendicular electric field. This work is useful for designing heterojunctions and heterostructures made of graphene and other two-dimensional materials such as those proposed in recent experiments [X. Liu and M. C. Hersam Sci. Adv. 5, 6444 (2019)].  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000515659700007 Publication Date 2020-02-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.7 Times cited 24 Open Access  
  Notes ; ; Approved Most recent IF: 3.7; 2020 IF: 3.836  
  Call Number UA @ admin @ c:irua:167760 Serial 6640  
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Author (up) Bafekry, A.; Neek-Amal, M.; Peeters, F.M. url  doi
openurl 
  Title Two-dimensional graphitic carbon nitrides: strain-tunable ferromagnetic ordering Type A1 Journal article
  Year 2020 Publication Physical Review B Abbreviated Journal Phys Rev B  
  Volume 101 Issue 16 Pages 165407-165408  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using first-principle calculations, we systematically study strain tuning of the electronic properties of two- dimensional graphitic carbon nitride nanosheets with empirical formula CnNm. We found the following: (i) the ferromagnetic ordered state in the metal-free systems (n, m) = (4,3), (10,9), and (14,12) remains stable in the presence of strain of about 6%. However, the system (9,7) loses its ferromagnetic ordering when increasing strain. This is due to the presence of topological defects in the (9,7) system, which eliminates the asymmetry between spin up and spin down of the p(z) orbitals when strain is applied. (ii) By applying uniaxial strain, a band gap opens in systems which are initially gapless. (iii) In semiconducting systems which have an initial gap of about 1 eV, the band gap is closed with applying uniaxial strain.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000523630200012 Publication Date 2020-04-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.7 Times cited 22 Open Access  
  Notes ; ; Approved Most recent IF: 3.7; 2020 IF: 3.836  
  Call Number UA @ admin @ c:irua:168560 Serial 6643  
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Author (up) Bafekry, A.; Nguyen, C., V; Goudarzi, A.; Ghergherehchi, M.; Shafieirad, M. url  doi
openurl 
  Title Investigation of strain and doping on the electronic properties of single layers of C₆N₆ and C₆N₈: a first principles study Type A1 Journal article
  Year 2020 Publication Rsc Advances Abbreviated Journal Rsc Adv  
  Volume 10 Issue 46 Pages 27743-27751  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this work, by performing first-principles calculations, we explore the effects of various atom impurities on the electronic and magnetic properties of single layers of C(6)N(6)and C6N8. Our results indicate that atom doping may significantly modify the electronic properties. Surprisingly, doping Cr into a holey site of C(6)N(6)monolayer was found to exhibit a narrow band gap of 125 meV upon compression strain, considering the spin-orbit coupling effect. Also, a C atom doped in C(6)N(8)monolayer shows semi-metal nature under compression strains larger than -2%. Our results propose that Mg or Ca doped into strained C(6)N(6)may exhibit small band gaps in the range of 10-30 meV. In addition, a magnetic-to-nonmagnetic phase transition can occur under large tensile strains in the Ca doped C(6)N(8)monolayer. Our results highlight the electronic properties and magnetism of C(6)N(6)and C(6)N(8)monolayers. Our results show that the electronic properties can be effectively modified by atom doping and mechanical strain, thereby offering new possibilities to tailor the electronic and magnetic properties of C(6)N(6)and C(6)N(8)carbon nitride monolayers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000553911800053 Publication Date 2020-07-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2046-2069 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.9 Times cited 11 Open Access  
  Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (NRF-2017R1A2B2011989). ; Approved Most recent IF: 3.9; 2020 IF: 3.108  
  Call Number UA @ admin @ c:irua:172111 Serial 6553  
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Author (up) Bafekry, A.; Nguyen, C.; Obeid, M.M.; Ghergherehchi, M. url  doi
openurl 
  Title Modulating the electro-optical properties of doped C₃N monolayers and graphene bilayersviamechanical strain and pressure Type A1 Journal article
  Year 2020 Publication New Journal Of Chemistry Abbreviated Journal New J Chem  
  Volume 44 Issue 36 Pages 15785-15792  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this work, we investigated systematically the electronic and optical properties of B doped C3N monolayers as well as B and N doped graphene bilayers (BN-Gr@2L). We found that the doping of B atoms leads to an enlarged band gap of the C3N monolayer and when the dopant concentration reaches 12.5%, an indirect-to-direct band gap switching occurs. In addition, with co-doping of B and N atoms on the graphene monolayer in the hexagonal configuration, an electronic transition from semi-metal to semiconductor occurs. Our optical results for B-C3N show a broad absorption spectrum in a wide visible range starting from 400 nm to 1000 nm with strong absorption intensity, making it a suitable candidate for nanoelectronic and optoelectronic applications. Interestingly, a transition from semi-metal to semiconductor emerges in the graphene monolayer with doping of B and N atoms. Furthermore, our results demonstrate that the in-plane strain and out-of-plane strain (pressure) can modulate the band gap of the BN-Gr@2L. The controllable electronic properties and optical features of the doped graphene bilayer by strain engineering may facilitate their practical performance for various applications in future.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000571972400054 Publication Date 2020-08-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1144-0546 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.3 Times cited 7 Open Access  
  Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (NRF-2017R1A2B2011989). ; Approved Most recent IF: 3.3; 2020 IF: 3.269  
  Call Number UA @ admin @ c:irua:171936 Serial 6561  
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Author (up) Bafekry, A.; Obeid, M.; Nguyen, C.; Bagheri Tagani, M.; Ghergherehchi, M. url  doi
openurl 
  Title Graphene hetero-multilayer on layered platinum mineral Jacutingaite (Pt₂HgSe₃): Van der Waals heterostructures with novel optoelectronic and thermoelectric performances Type A1 Journal article
  Year 2020 Publication Journal Of Materials Chemistry A Abbreviated Journal J Mater Chem A  
  Volume 8 Issue 26 Pages 13248-13260  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Motivated by the recent successful synthesis of the layered platinum mineral jacutingaite (Pt2HgSe3), we have studied the optoelectronic, mechanical, and thermoelectric properties of graphene hetero-multilayer on Pt(2)HgSe(3)monolayer (PHS) heterostructures (LG/PHS) by using first-principles calculations. PHS is a topological insulator with a band gap of about 160 meV with fully relativistic calculations; when graphene layers are stacked on PHS, a narrow band gap of similar to 10-15 meV opens. In the presence of gate-voltage and out-of plane strain,i.e.pressure, the electronic properties are modified; the Dirac-cone of graphene can be shifted upwards (downward) to a lower (higher) binding energy. The absorption spectrum shows two peaks, which are located around 216 nm (5.74 eV) and protracted to 490 nm (2.53 eV), indicating that PHS could absorb more visible light. Increasing the number of graphene layers on PHS has a positive impact on the UV-vis light absorption and gives a clear red-shift with enhanced absorption intensity. To investigate the electronic performance of the heterostructure, the electrical conductance and thermopower of a device composed of graphene layers and PHS is examined by a combination of DFT and Green function formalism. The number of graphene layers can significantly tune the thermopower and electrical conductance. This analysis reveals that the heterostructures not only significantly affect the electronic properties, but they can also be used as an efficient way to modulate the optic and thermoelectric properties.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000546391600032 Publication Date 2020-05-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2050-7488; 2050-7496 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 11.9 Times cited 20 Open Access  
  Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea Government (MSIT) (NRF-2017R1A2B2011989) and Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 103.01-2019.05. ; Approved Most recent IF: 11.9; 2020 IF: 8.867  
  Call Number UA @ admin @ c:irua:169755 Serial 6529  
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Author (up) Bafekry, A.; Sarsari, I.A.; Faraji, M.; Fadlallah, M.M.; Jappor, H.R.; Karbasizadeh, S.; Nguyen, V.; Ghergherehchi, M. url  doi
openurl 
  Title Electronic and magnetic properties of two-dimensional of FeX (X = S, Se, Te) monolayers crystallize in the orthorhombic structures Type A1 Journal article
  Year 2021 Publication Applied Physics Letters Abbreviated Journal Appl Phys Lett  
  Volume 118 Issue 14 Pages 143102  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this Letter, we explore the lattice, dynamical stability, and electronic and magnetic properties of FeTe bulk and FeX (X=S, Se, Te) monolayers using the density functional calculations. The phonon dispersion relation, elastic stability criteria, and cohesive energy results show the stability of studied FeX monolayers. The mechanical properties reveal that all FeX monolayers have a brittle nature. Furthermore, these structures are stable as we move down the 6A group in the periodic table, i.e., from S, Se, and Te. The stability and work function decrease as the electronegativity decreases. The spin-polarized electronic structures demonstrate that the FeTe monolayer has a total magnetization of 3.8 mu (B), which is smaller than the magnetization of FeTe bulk (4.7 mu (B)). However, FeSe and FeS are nonmagnetic monolayers. The FeTe monolayer can be a good candidate material for spin filter applications due to its electronic and magnetic properties. This study highlights the bright prospect for the application of FeX monolayers in electronic structures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000637703700001 Publication Date 2021-04-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6951; 1077-3118 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.411  
  Call Number UA @ admin @ c:irua:177731 Serial 6985  
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Author (up) Bafekry, A.; Shahrokhi, M.; Shafique, A.; Jappor, H.R.; Fadlallah, M.M.; Stampfl, C.; Ghergherehchi, M.; Mushtaq, M.; Feghhi, S.A.H.; Gogova, D. url  doi
openurl 
  Title Semiconducting chalcogenide alloys based on the (Ge, Sn, Pb) (S, Se, Te) formula with outstanding properties : a first-principles calculation study Type A1 Journal article
  Year 2021 Publication ACS Omega Abbreviated Journal  
  Volume 6 Issue 14 Pages 9433-9441  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Very recently, a new class of the multicationic and -anionic entropy-stabilized chalcogenide alloys based on the (Ge, Sn, Pb) (S, Se, Te) formula has been successfully fabricated and characterized experimentally [Zihao Deng et al., Chem. Mater. 32, 6070 (2020)]. Motivated by the recent experiment, herein, we perform density functional theory-based first-principles calculations in order to investigate the structural, mechanical, electronic, optical, and thermoelectric properties. The calculations of the cohesive energy and elasticity parameters indicate that the alloy is stable. Also, the mechanical study shows that the alloy has a brittle nature. The GeSnPbSSeTe alloy is a semiconductor with a direct band gap of 0.4 eV (0.3 eV using spin-orbit coupling effect). The optical analysis illustrates that the first peak of Im(epsilon) for the GeSnPbSSeTe alloy along all polarization directions is located in the visible range of the spectrum which renders it a promising material for applications in optical and electronic devices. Interestingly, we find an optically anisotropic character of this system which is highly desirable for the design of polarization-sensitive photodetectors. We have accurately predicted the thermoelectric coefficients and have calculated a large power factor value of 3.7 x 10(11) W m(-1) K-2 s(-1) for p-type. The high p-type power factor is originated from the multiple valleys near the valence band maxima. The anisotropic results of the optical and transport properties are related to the specific tetragonal alloy unit cell.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000640649500012 Publication Date 2021-03-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-1343 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:178395 Serial 7017  
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Author (up) Bafekry, A.; Shahrokhi, M.; Shafique, A.; Jappor, H.R.; Shojaei, F.; Feghhi, S.A.H.; Ghergherehchi, M.; Gogova, D. pdf  url
doi  openurl
  Title Two-dimensional carbon nitride C₆N nanosheet with egg-comb-like structure and electronic properties of a semimetal Type A1 Journal article
  Year 2021 Publication Nanotechnology Abbreviated Journal Nanotechnology  
  Volume 32 Issue 21 Pages 215702  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract In this study, the structural, electronic and optical properties of theoretically predicted C6N monolayer structure are investigated by means of Density Functional Theory-based First-Principles Calculations. Phonon band dispersion calculations and molecular dynamics simulations reveal the dynamical and thermal stability of the C6N single-layer structure. We found out that the C6N monolayer has large negative in-plane Poisson's ratios along both X and Y direction and the both values are almost four times that of the famous-pentagraphene. The electronic structure shows that C6N monolayer is a semi-metal and has a Dirac-point in the BZ. The optical analysis using the random phase approximation method constructed over HSE06 illustrates that the first peak of absorption coefficient of the C6N monolayer along all polarizations is located in the IR range of spectrum, while the second absorption peak occurs in the visible range, which suggests its potential applications in optical and electronic devices. Interestingly, optically anisotropic character of this system is highly desirable for the design of polarization-sensitive photodetectors. Thermoelectric properties such as Seebeck coefficient, electrical conductivity, electronic thermal conductivity and power factor are investigated as a function of carrier doping at temperatures 300, 400, and 500 K. In general, we predict that the C6N monolayer could be a new platform for study of novel physical properties in two-dimensional semi-metal materials, which may provide new opportunities to realize high-speed low-dissipation devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000624531500001 Publication Date 2020-12-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.44 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.44  
  Call Number UA @ admin @ c:irua:176648 Serial 6740  
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Author (up) Bafekry, A.; Shahrokhi, M.; Yagmurcukardes, M.; Gogova, D.; Ghergherehchi, M.; Akgenc, B.; Feghhi, S.A.H. pdf  url
doi  openurl
  Title Surface functionalization of the honeycomb structure of zinc antimonide (ZnSb) monolayer : a first-principles study Type A1 Journal article
  Year 2021 Publication Surface Science Abbreviated Journal Surf Sci  
  Volume 707 Issue Pages 121796  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Structural, electronic, optic and vibrational properties of Zinc antimonide (ZnSb) monolayers and their func-tionalized (semi-fluorinated and fully chlorinated) structures are investigated by means of the first-principles calculations. The phonon dispersion curves reveal the presence of imaginary frequencies and thus confirm the dynamical instability of ZnSb monolayer. The calculated electronic band structure corroborates the metallic character with fully-relativistic calculations. Moreover, we analyze the surface functionalization effect on the structural, vibrational, and electronic properties of the pristine ZnSb monolayer. The semi-fluorinated and fully-chlorinated ZnSb monolayers are shown to be dynamically stable in contrast to the ZnSb monolayer. At the same time, semi-fluorination and fully-chlorination of ZnSb monolayer could effectively modulate the metallic elec-tronic properties of pristine ZnSb. In addition, a magnetic metal to a nonmagnetic semiconductor transition with a band gap of 1 eV is achieved via fluorination, whereas a transition to a semiconducting state with 1.4 eV band gap is found via chlorination of the ZnSb monolayer. According to the optical properties analysis, the first ab-sorption peaks of the fluorinated-and chlorinated-ZnSb monolayers along the in-plane polarization are placed in the infrared range of spectrum, while they are in the middle ultraviolet for the out-of-plane polarization. Interestingly, the optically anisotropic behavior of these novel monolayers along the in-plane polarizations is highly desirable for design of polarization-sensitive photodetectors. The results of the calculations clearly proved that the tunable electronic properties of the ZnSb monolayer can be realized by chemical functionalization for application in the next generation nanoelectronic devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000626633500001 Publication Date 2020-12-31  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0039-6028 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.062 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 2.062  
  Call Number UA @ admin @ c:irua:177623 Serial 7026  
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Author (up) Bafekry, A.; Shayesteh, S.F.; Ghergherehchi, M.; Peeters, F.M. pdf  doi
openurl 
  Title Tuning the bandgap and introducing magnetism into monolayer BC3 by strain/defect engineering and adatom/molecule adsorption Type A1 Journal article
  Year 2019 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 126 Issue 14 Pages 144304  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using first-principles calculations, we study the structural, electronic, and optical properties of pristine BC3. Our results show that BC3 is a semiconductor which can be useful in optoelectronic device applications. Furthermore, we found that the electronic properties of BC3 can be modified by strain and the type of edge states. With increasing thickness, the indirect bandgap decreases from 0.7 eV (monolayer) to 0.27 eV (bulk). Upon uniaxial tensile strain along the armchair and zigzag directions, the bandgap slightly decreases, and with increasing uniaxial strain, the bandgap decreases, and when reaching -8%, a semiconductor-to-metal transition occurs. By contrast, under biaxial strain, the bandgap increases to 1.2 eV in +8% and decreases to zero in -8%. BC3 nanoribbons with different widths exhibit magnetism at the zigzag edges, while, at the armchair edges, they become semiconductor, and the bandgap is in the range of 1.0-1.2 eV. Moreover, we systematically investigated the effects of adatoms/molecule adsorption and defects on the structural, electronic, and magnetic properties of BC3. The adsorption of various adatoms and molecules as well as topological defects (vacancies and Stone-Wales defects) can modify the electronic properties. Using these methods, one can tune BC3 into a metal, half-metal, ferromagnetic-metal, and dilute-magnetic semiconductor or preserve its semiconducting character. Published under license by AIP Publishing.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000503995300019 Publication Date 2019-10-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 48 Open Access  
  Notes Approved Most recent IF: 2.068  
  Call Number UA @ admin @ c:irua:165160 Serial 6328  
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Author (up) Bafekry, A.; Shayesteh, S.F.; Peeters, F.M. url  doi
openurl 
  Title C3N Monolayer: Exploring the Emerging of Novel Electronic and Magnetic Properties with Adatom Adsorption, Functionalizations, Electric Field, Charging, and Strain Type A1 Journal article
  Year 2019 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C  
  Volume 123 Issue 19 Pages 12485-12499  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Two-dimensional polyaniline with structural unit C3N is an indirect semiconductor with 0.4 eV band gap, which has attracted a lot of interest because of its unusual electronic, optoelectronic, thermal, and mechanical properties useful for various applications. Adsorption of adatoms is an effective method to improve and tune the properties of C3N. Using first-principles calculations, we investigated the adsorption of adatoms, including H, O, S, F, Cl, B, C, Si, N, P, Al, Li, Na, K, Be, Mg, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn, on C3N. Depending on the adatom size and the number of valence electrons, they may induce metallic, half-metallic, semiconducting, and ferromagnetic-metallic behavior. In addition, we investigate the effects of an electrical field, charging, and strain on C3N and found how the electronic and magnetic properties are modified. Semi- and full hydrogenation are studied. From the mechanical and thermal stability of C3N monolayer, we found it to be a hard material that can withstand large strain. From our calculations, we gained novel insights into the properties of C3N demonstrating its unique electronic and magnetic properties that can be useful for semiconducting, nanosensor, and catalytic applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000468368800053 Publication Date 2019-04-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-7447; 1932-7455 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.536 Times cited 67 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FW0-V1). The authors thank Keyvan Nazifi from the Cluster Center of Faculty of Science, Guilan University, for his help. They acknowledge OpenMX team for OpenMX code. ; Approved Most recent IF: 4.536  
  Call Number UA @ admin @ c:irua:160323 Serial 5196  
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Author (up) Bafekry, A.; Shayesteh, S.F.; Peeters, F.M. url  doi
openurl 
  Title Introducing novel electronic and magnetic properties in C3N nanosheets by defect engineering and atom substitution Type A1 Journal article
  Year 2019 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 21 Issue 37 Pages 21070-21083  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using first-principles calculations the effect of topological defects, vacancies, Stone-Wales and anti-site and substitution of atoms, on the structure and electronic properties of monolayer C3N are investigated. Vacancy defects introduce localized states near the Fermi level and a local magnetic moment. While pristine C3N is an indirect semiconductor with a 0.4 eV band gap, with substitution of O, S and Si atoms for C, it remains a semiconductor with a band gap in the range 0.25-0.75 eV, while it turns into a metal with H, Cl, B, P, Li, Na, K, Be and Mg substitution. With F substitution, it becomes a dilute-magnetic semiconductor, while with Ca substitution it is a ferromagnetic-metal. When replacing the N host atom, C3N turns into: a metal (H, O, S, C, Si, P, Li and Be), ferromagnetic-metal (Mg), half-metal (Ca) and spin-glass semiconductor (Na and K). Moreover, the effects of charging and strain on the electronic properties of Na atom substitution in C3N are investigated. We found that the magnetic moment decreases or increases depending on the type and size of strain (tensile or compression). Our study shows how the band gap and magnetism in monolayer C3N can be tuned by introducing defects and atom substitution. The so engineered C3N can be a good candidate for future low dimensional devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000489984200050 Publication Date 2019-09-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.123 Times cited 52 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:163732 Serial 5418  
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Author (up) Bafekry, A.; Shayesteh, S.F.; Peeters, F.M. url  doi
openurl 
  Title Two-dimensional carbon nitride (2DCN) nanosheets : tuning of novel electronic and magnetic properties by hydrogenation, atom substitution and defect engineering Type A1 Journal article
  Year 2019 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 126 Issue 21 Pages 215104  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract By employing first-principles calculations within the framework of density functional theory, we investigated the structural, electronic, and magnetic properties of graphene and various two-dimensional carbon-nitride (2DNC) nanosheets. The different 2DCN gives rise to diverse electronic properties such as metals (C3N2), semimetals (C4N and C9N4), half-metals (C4N3), ferromagnetic-metals (C9N7), semiconductors (C2N, C3N, C3N4, C6N6, and C6N8), spin-glass semiconductors (C10N9 and C14N12), and insulators (C2N2). Furthermore, the effects of adsorption and substitution of hydrogen atoms as well as N-vacancy defects on the electronic and magnetic properties are systematically studied. The introduction of point defects, including N vacancies, interstitial H impurity into graphene and different 2DCN crystals, results in very different band structures. Defect engineering leads to the discovery of potentially exotic properties that make 2DCN interesting for future investigations and emerging technological applications with precisely tailored properties. These properties can be useful for applications in various fields such as catalysis, energy storage, nanoelectronic devices, spintronics, optoelectronics, and nanosensors. Published under license by AIP Publishing.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000504007300023 Publication Date 2019-12-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 57 Open Access  
  Notes Approved Most recent IF: 2.068  
  Call Number UA @ admin @ c:irua:165733 Serial 6329  
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Author (up) Bafekry, A.; Shojaei, F.; Obeid, M.M.; Ghergherehchi, M.; Nguyen, C.; Oskouian, M. url  doi
openurl 
  Title Two-dimensional silicon bismotide (SiBi) monolayer with a honeycomb-like lattice: first-principles study of tuning the electronic properties Type A1 Journal article
  Year 2020 Publication Rsc Advances Abbreviated Journal Rsc Adv  
  Volume 10 Issue 53 Pages 31894-31900  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using density functional theory, we investigate a novel two-dimensional silicon bismotide (SiBi) that has a layered GaSe-like crystal structure.Ab initiomolecular dynamic simulations and phonon dispersion calculations suggest its good thermal and dynamical stability. The SiBi monolayer is a semiconductor with a narrow indirect bandgap of 0.4 eV. Our results show that the indirect bandgap decreases as the number of layers increases, and when the number of layers is more than six layers, direct-to-indirect bandgap switching occurs. The SiBi bilayer is found to be very sensitive to an E-field. The bandgap monotonically decreases in response to uniaxial and biaxial compressive strain, and reaches 0.2 eV at 5%, while at 6%, the semiconductor becomes a metal. For both uniaxial and biaxial tensile strains, the material remains a semiconductor and indirect-to-direct bandgap transition occurs at a strain of 3%. Compared to a SiBi monolayer with a layer thickness of 4.89 angstrom, the bandgap decreases with either increasing or decreasing layer thickness, and at a thicknesses of 4.59 to 5.01 angstrom, the semiconductor-to-metal transition happens. In addition, under pressure, the semiconducting character of the SiBi bilayer with a 0.25 eV direct bandgap is preserved. Our results demonstrate that the SiBi nanosheet is a promising candidate for designing high-speed low-dissipation devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000565206400027 Publication Date 2020-09-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2046-2069 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.9 Times cited 8 Open Access  
  Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant, funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). ; Approved Most recent IF: 3.9; 2020 IF: 3.108  
  Call Number UA @ admin @ c:irua:172045 Serial 6644  
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Author (up) Bafekry, A.; Shojai, F.; Hoat, D.M.; Shahrokhi, M.; Ghergherehchi, M.; Nguyen, C. url  doi
openurl 
  Title The mechanical, electronic, optical and thermoelectric properties of two-dimensional honeycomb-like of XSb (X = Si, Ge, Sn) monolayers: a first-principles calculations Type A1 Journal article
  Year 2020 Publication Rsc Advances Abbreviated Journal Rsc Adv  
  Volume 10 Issue 51 Pages 30398-30405  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Herein, by using first-principles calculations, we demonstrate a two-dimensional (2D) of XSb (X = Si, Ge, and Sn) monolayers that have a honey-like crystal structure. The structural, mechanical, electronic, thermoelectric efficiency, and optical properties of XSb monolayers are studied.Ab initiomolecular dynamic simulations and phonon dispersion calculations suggests their good thermal and dynamical stabilities. The mechanical properties of XSb monolayers shows that the monolayers are considerably softer than graphene, and their in-plane stiffness decreases from SiSb to SnSb. Our results shows that the single layers of SiSb, GeSb and SnSb are semiconductor with band gap of 1.48, 0.77 and 0.73 eV, respectively. The optical analysis illustrate that the first absorption peaks of the SiSb, GeSb and SnSb monolayers along the in-plane polarization are located in visible range of light which may serve as a promising candidate to design advanced optoelectronic devices. Thermoelectric properties of the XSb monolayers, including Seebeck coefficient, electrical conductivity, electronic thermal conductivity, power factor and figure of merit are calculated as a function of doping level at temperatures of 300 K and 800 K. Between the studied two-dimensional materials (2DM), SiSb single layer may be the most promising candidate for application in the thermoelectric generators.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000561344000009 Publication Date 2020-08-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2046-2069 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.9 Times cited 2 Open Access  
  Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). ; Approved Most recent IF: 3.9; 2020 IF: 3.108  
  Call Number UA @ admin @ c:irua:172074 Serial 6624  
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Author (up) Bafekry, A.; Stampfl, C.; Akgenc, B.; Ghergherehchi, M. url  doi
openurl 
  Title Control of C3N4 and C4N3 carbon nitride nanosheets' electronic and magnetic properties through embedded atoms Type A1 Journal article
  Year 2020 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 22 Issue 4 Pages 2249-2261  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In the present work, the effect of various embedded atom impurities on tuning electronic and magnetic properties of C3N4 and C4N3 nanosheets have been studied using first-principles calculations. Our calculations show that C3N4 is a semiconductor and it exhibits extraordinary electronic properties such as dilute-magnetic semiconductor (with H, F, Cl, Be, V, Fe and Co); metal (with N, P, Mg and Ca), half-metal (with Li, Na, K, Al, Sc, Cr, Mn, and Cu) and semiconductor (with O, S, B, C, Si, Ti, Ni and Zn) with the band gaps in the range of 0.3-2.0 eV depending on the species of embedded atom. The calculated electronic properties reveal that C4N3 is a half-metal and it retains half-metallic character with embedded H, O, S, F, B, N, P, Be, Mg, Al, Sc, V, Fe, Ni and Zn atoms. The substitution of Cl, C, Cr and Mn atoms create ferromagnetic-metal character in the C4N3 nanosheet, embedded Co and Cu atoms exhibit a dilute-magnetic semiconductor nature, and embedded Ti atoms result in the system becoming a semiconductor. Therefore, our results reveal the fact that the band gap and magnetism can be modified or induced by various atom impurities, thus, offering effective possibilities to tune the electronic and magnetic properties of C3N4 and C4N3 nanosheets.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000510729400042 Publication Date 2019-12-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.3 Times cited 18 Open Access  
  Notes ; This work has supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). B. Akgenc acknowledges financial support the Kirklareli University-BAP under the Project No 189 and TUBITAK ULAKBIM, High Performance and Grid Computing Center. ; Approved Most recent IF: 3.3; 2020 IF: 4.123  
  Call Number UA @ admin @ c:irua:166553 Serial 6476  
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Author (up) Bafekry, A.; Stampfl, C.; Akgenc, B.; Mortazavi, B.; Ghergherehchi, M.; Nguyen, C.V. url  doi
openurl 
  Title Embedding of atoms into the nanopore sites of the C₆N₆ and C₆N₈ porous carbon nitride monolayers with tunable electronic properties Type A1 Journal article
  Year 2020 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 22 Issue 11 Pages 6418-6433  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using first-principles calculations, we study the effect of embedding various atoms into the nanopore sites of both C6N6 and C6N8 monolayers. Our results indicate that the embedded atoms significantly affect the electronic and magnetic properties of C6N6 and C6N8 monolayers and lead to extraordinary and multifarious electronic properties, such as metallic, half-metallic, spin-glass semiconductor and dilute-magnetic semiconductor behaviour. Our results reveal that the H atom concentration dramatically affects the C6N6 monolayer. On increasing the H coverage, the impurity states also increase due to H atoms around the Fermi-level. C6N6 shows metallic character when the H atom concentration reaches 6.25%. Moreover, the effect of charge on the electronic properties of both Cr@C6N6 and C@C6N8 is also studied. Cr@C6N6 is a ferromagnetic metal with a magnetic moment of 2.40 mu(B), and when 0.2 electrons are added and removed, it remains a ferromagnetic metal with a magnetic moment of 2.57 and 2.77 mu(B), respectively. Interestingly, one can observe a semi-metal, in which the VBM and CBM in both spin channels touch each other near the Fermi-level. C@C6N8 is a semiconductor with a nontrivial band gap. When 0.2 electrons are removed, it remains metallic, and under excess electronic charge, it exhibits half-metallic behaviour.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000523409400037 Publication Date 2020-02-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.3 Times cited 17 Open Access  
  Notes ; This work was supported by a National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (NRF-2017R1A2B2011989). ; Approved Most recent IF: 3.3; 2020 IF: 4.123  
  Call Number UA @ admin @ c:irua:168617 Serial 6504  
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Author (up) Bafekry, A.; Stampfl, C.; Faraji, M.; Yagmurcukardes, M.; Fadlallah, M.M.; Jappor, H.R.; Ghergherehchi, M.; Feghhi, S.A.H. doi  openurl
  Title A Dirac-semimetal two-dimensional BeN4 : thickness-dependent electronic and optical properties Type A1 Journal article
  Year 2021 Publication Applied Physics Letters Abbreviated Journal Appl Phys Lett  
  Volume 118 Issue 20 Pages 203103  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Motivated by the recent experimental realization of a two-dimensional (2D) BeN4 monolayer, in this study we investigate the structural, dynamical, electronic, and optical properties of a monolayer and few-layer BeN4 using first-principles calculations. The calculated phonon band dispersion reveals the dynamical stability of a free-standing BeN4 layer, while the cohesive energy indicates the energetic feasibility of the material. Electronic band dispersions show that monolayer BeN4 is a semi-metal whose conduction and valence bands touch each other at the Sigma point. Our results reveal that increasing the layer number from single to six-layers tunes the electronic nature of BeN4. While monolayer and bilayer structures display a semi-metallic behavior, structures thicker than that of three-layers exhibit a metallic nature. Moreover, the optical parameters calculated for monolayer and bilayer structures reveal that the bilayer can absorb visible light in the ultraviolet and visible regions better than the monolayer structure. Our study investigates the electronic properties of Dirac-semimetal BeN4 that can be an important candidate for applications in nanoelectronic and optoelectronic. Published under an exclusive license by AIP Publishing.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000691329900002 Publication Date 2021-05-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6951; 1077-3118 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 3.411  
  Call Number UA @ admin @ c:irua:181725 Serial 6980  
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Author (up) Bafekry, A.; Stampfl, C.; Ghergherehchi, M. pdf  url
doi  isbn
openurl 
  Title Strain, electric-field and functionalization induced widely tunable electronic properties in MoS2/BC3, /C3N and / C3N4 van der Waals heterostructures Type A1 Journal article
  Year 2020 Publication Nanotechnology (Bristol. Print) Abbreviated Journal  
  Volume Issue Pages 295202 pp  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract In this paper, the effect of BC3, C3N and C3N4BC(3) and MoS2/C(3)N4 heterostructures are direct semiconductors with band gaps of 0.4 and 1.74 eV, respectively, while MoS2/C3N is a metal. Furthermore, the influence of strain and electric field on the electronic structure of these van der Waals heterostructures is investigated. The MoS2/BC3 heterostructure, for strains larger than -4%, transforms it into a metal where the metallic character is maintained for strains larger than -6%. The band gap decreases with increasing strain to 0.35 eV (at +2%), while for strain (>+6%) a direct-indirect band gap transition is predicted to occur. For the MoS2/C3N heterostructure, the metallic character persists for all strains considered. On applying an electric field, the electronic properties of MoS2/C3N4 are modified and its band gap decreases as the electric field increases. Interestingly, the band gap reaches 30 meV at +0.8 V/angstrom, and with increase above +0.8 V/angstrom, a semiconductor-to-metal transition occurs. Furthermore, we investigated effects of semi- and full-hydrogenation of MoS2/C3N and we found that it leads to a metallic and semiconducting character, respectively.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000532366000001 Publication Date 2020-04-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 0957-4484 Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 19 Open Access  
  Notes ; This work has supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT)(NRF-2017R1A2B2011989). ; Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:169523 Serial 6444  
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Author (up) Bafekry, A.; Stampfl, C.; Ghergherehchi, M.; Shayesteh, S.F. pdf  url
doi  openurl
  Title A first-principles study of the effects of atom impurities, defects, strain, electric field and layer thickness on the electronic and magnetic properties of the C2N nanosheet Type A1 Journal article
  Year 2020 Publication Carbon Abbreviated Journal Carbon  
  Volume 157 Issue 157 Pages 371-384  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using the first-principles calculations, we explore the structural and novel electronic/optical properties of the C2N nanosheet. To this goal, we systematically investigate the affect of layer thickness, electrical field and strain on the electronic properties of the C2N nanosheet. By increasing the thickness of C2N, we observed that the band gap decreases. Moreover, by applying an electrical field to bilayer C2N, the band gap decreases and a semiconductor-to-metal transition can occur. Our results also confirm that uniaxial and biaxial strain can effectively alter the band gap of C2N monolayer. Furthermore, we show that the electronic and magnetic properties of C2N can be modified by the adsorption and substitution of various atoms. Depending on the species of embedded atoms, they may induce semiconductor (O, C, Si and Be), metal (S, N, P, Na, K, Mg and Ca), dilute-magnetic semiconductor (H, F, B), or ferro-magnetic-metal (Cl, Li) character in C2N monolayer. It was also found that the inclusion of hydrogen or oxygen impurities and nitrogen vacancies, can induce magnetism in the C2N monolayer. These extensive calculations can be useful to guide future studies to modify the electronic/optical properties of two-dimensional materials. (C) 2019 Elsevier Ltd. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000502548500044 Publication Date 2019-10-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0008-6223 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 10.9 Times cited 49 Open Access  
  Notes ; This work was supported by the National Research Foundation of Korea grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). We are thankful for comments by Meysam Baghery Tagani from department of physics in University of Guilan and Bohayra Mortazavi from Gottfried Wilhelm Leibniz Universitat Hannover, Hannover, Germany. ; Approved Most recent IF: 10.9; 2020 IF: 6.337  
  Call Number UA @ admin @ c:irua:165024 Serial 6283  
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Author (up) Bafekry, A.; Stampfl, C.; Naseri, M.; Fadlallah, M.M.; Faraji, M.; Ghergherehchi, M.; Gogova, D.; Feghhi, S.A.H. url  doi
openurl 
  Title Effect of electric field and vertical strain on the electro-optical properties of the MoSi2N4 bilayer : a first-principles calculation Type A1 Journal article
  Year 2021 Publication Journal Of Applied Physics Abbreviated Journal J Appl Phys  
  Volume 129 Issue 15 Pages 155103  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Recently, a two-dimensional (2D) MoSi 2N 4 (MSN) structure has been successfully synthesized [Hong et al., Science 369(6504), 670-674 (2020)]. Motivated by this result, we investigate the structural, electronic, and optical properties of MSN monolayer (MSN-1L) and bilayer (MSN-2L) under the applied electric field (E-field) and strain using density functional theory calculations. We find that the MSN-2L is a semiconductor with an indirect bandgap of 1.60 (1.80)eV using Perdew-Burke-Ernzerhof (HSE06). The bandgap of MSN-2L decreases as the E-field increases from 0.1 to 0.6V/angstrom and for larger E-field up to 1.0V/angstrom the bilayer becomes metallic. As the vertical strain increases, the bandgap decreases; more interestingly, a semiconductor to a metal phase transition is observed at a strain of 12 %. Furthermore, the optical response of the MSN-2L is in the ultraviolet (UV) region of the electromagnetic spectrum. The absorption edge exhibits a blue shift by applying an E-field or a vertical compressive strain. The obtained interesting properties suggest MSN-2L as a promising material in electro-mechanical and UV opto-mechanical devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000640620400003 Publication Date 2021-04-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 2.068  
  Call Number UA @ admin @ c:irua:178233 Serial 6981  
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Author (up) Bafekry, A.; Stampfl, C.; Peeters, F.M. url  doi
openurl 
  Title Dirac half-metallicity of thin PdCl₃ nanosheets : investigation of the effects of external fields, surface adsorption and defect engineering on the electronic and magnetic properties Type A1 Journal article
  Year 2020 Publication Scientific Reports Abbreviated Journal Sci Rep-Uk  
  Volume 10 Issue 1 Pages 213-215  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract PdCl3 belongs to a novel class of Dirac materials with Dirac spin-gapless semiconducting characteristics. In this paper based, on first-principles calculations, we have systematically investigated the effect of adatom adsorption, vacancy defects, electric field, strain, edge states and layer thickness on the electronic and magnetic properties of PdCl3 (palladium trichloride). Our results show that when spin-orbital coupling is included, PdCl3 exhibits the quantum anomalous Hall effect with a non-trivial band gap of 24 meV. With increasing number of layers, from monolayer to bulk, a transition occurs from a Dirac half-metal to a ferromagnetic metal. On application of a perpendicular electrical field to bilayer PdCl3, we find that the energy band gap decreases with increasing field. Uniaxial and biaxial strain, significantly modifies the electronic structure depending on the strain type and magnitude. Adsorption of adatom and topological defects have a dramatic effect on the electronic and magnetic properties of PdCl3. In particular, the structure can become a metal (Na), half-metal (Be, Ca, Al, Ti, V, Cr, Fe and Cu with, respective, 0.72, 9.71, 7.14, 6.90, 9.71, 4.33 and 9.5 μB magnetic moments), ferromagnetic-metal (Sc, Mn and Co with 4.55, 7.93 and 2.0 μB), spin-glass semiconductor (Mg, Ni with 3.30 and 8.63 μB), and dilute-magnetic semiconductor (Li, K and Zn with 9.0, 9.0 and 5.80 μB magnetic moment, respectively). Single Pd and double Pd + Cl vacancies in PdCl3 display dilute-magnetic semiconductor characteristics, while with a single Cl vacancy, the material becomes a half-metal. The calculated optical properties of PdCl3 suggest it could be a good candidate for microelectronic and optoelectronics devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000562795700001 Publication Date 2020-01-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.6 Times cited 26 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). We are thankful for comments by Sevil Sarikurt from the department of physics in Dokuz Eylul University. In addition, we acknowledge OpenMX team for OpenMX code. ; Approved Most recent IF: 4.6; 2020 IF: 4.259  
  Call Number UA @ admin @ c:irua:169751 Serial 6483  
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Author (up) Bafekry, A.; Stampfl, C.; Peeters, F.M. pdf  doi
openurl 
  Title The electronic, optical, and thermoelectric properties of monolayer PbTe and the tunability of the electronic structure by external fields and defects Type A1 Journal article
  Year 2020 Publication Physica Status Solidi B-Basic Solid State Physics Abbreviated Journal Phys Status Solidi B  
  Volume Issue Pages 2000182-12  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract First‐principles calculations, within the framework of density functional theory, are used to investigate the structural, electronic, optical, and thermoelectric properties of monolayer PbTe. The effect of layer thickness, electric field, strain, and vacancy defects on the electronic and magnetic properties is systematically studied. The results show that the bandgap decreases as the layer thickness increases from monolayer to bulk. With application of an electric field on bilayer PbTe, the bandgap decreases from 70 meV (0.2 V Å⁻¹) to 50 meV (1 V Å⁻¹) when including spin–orbit coupling (SOC). Application of uniaxial strain induces a direct‐to‐indirect bandgap transition for strain greater than +6%. In addition, the bandgap decreases under compressive biaxial strain (with SOC). The effect of vacancy defects on the electronic properties of PbTe is also investigated. Such vacancy defects turn PbTe into a ferromagnetic metal (single vacancy Pb) with a magnetic moment of 1.3 μB, and into an indirect semiconductor with bandgap of 1.2 eV (single Te vacancy) and 1.5 eV (double Pb + Te vacancy). In addition, with change of the Te vacancy concentration, a bandgap of 0.38 eV (5.55%), 0.43 eV (8.33%), and 0.46 eV (11.11%) is predicted.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000527679200001 Publication Date 2020-04-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-1972 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.6 Times cited 37 Open Access  
  Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). In addition, this work was supported by the FLAG-ERA project 2DTRANS TMD and the Flemish Science Foundation (FWO-Vl). The authors are thankful for comments by Mohan Verma from the Computational Nanoionics Research Lab, Department of Applied Physics, Bhilai, India and to Francesco Buonocore from ENEA, Casaccia Research Centre, Rome, Italy. ; Approved Most recent IF: 1.6; 2020 IF: 1.674  
  Call Number UA @ admin @ c:irua:168730 Serial 6502  
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Author (up) Bafekry, A.; Stampfl, C.; Shayesteh, S.F. pdf  url
doi  openurl
  Title A first-principles study of C3N nanostructures : control and engineering of the electronic and magnetic properties of nanosheets, tubes and ribbons Type A1 Journal article
  Year 2020 Publication Chemphyschem Abbreviated Journal Chemphyschem  
  Volume 21 Issue 2 Pages 164-174  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using first-principles calculations we systematically investigate the atomic, electronic and magnetic properties of novel two-dimensional materials (2DM) with a stoichiometry C3N which has recently been synthesized. We investigate how the number of layers affect the electronic properties by considering monolayer, bilayer and trilayer structures, with different stacking of the layers. We find that a transition from semiconducting to metallic character occurs which could offer potential applications in future nanoelectronic devices. We also study the affect of width of C3N nanoribbons, as well as the radius and length of C3N nanotubes, on the atomic, electronic and magnetic properties. Our results show that these properties can be modified depending on these dimensions, and depend markedly on the nature of the edge states. Functionalization of the nanostructures by the adsorption of H adatoms is found induce metallic, half-metallic, semiconducting and ferromagnetic behavior, which offers an approach to tailor the properties, as can the application of strain. Our calculations give insight into this new family of C3N nanostructures, which reveal unusual electronic and magnetic properties, and may have great potential in applications such as sensors, electronics and optoelectronic at the nanoscale.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000503453100001 Publication Date 2019-11-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1439-4235 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.9 Times cited 27 Open Access  
  Notes ; ; Approved Most recent IF: 2.9; 2020 IF: 3.075  
  Call Number UA @ admin @ c:irua:165045 Serial 6282  
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Author (up) Bafekry, A.; Stampfl, C.; Shayesteh, S.F.; Peeters, F.M. pdf  doi
openurl 
  Title Exploiting the novel electronic and magnetic structure of C3Nvia functionalization and conformation Type A1 Journal article
  Year 2019 Publication Advanced Electronic Materials Abbreviated Journal Adv Electron Mater  
  Volume 5 Issue 5 Pages 1900459  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract 2D polyaniline, C3N, is of recent high interest due to its unusual properties and potential use in various technological applications. In this work, through systematic first-principles calculations, the atomic, electronic, and magnetic structure of C3N and the changes induced due to functionalization by the adsorption of hydrogen, oxygen, and fluorine, for different coverages and sites, as well as on formation of nanoribbons including the effect of adsorbed hydrogen and oxygen, and the effect of strain, are investigated. Among other interesting phenomena, for hydrogen adsorption, a semiconductor-to-topological insulator transition, where two Dirac-points appear around the Fermi level, as well as ferromagnetic ordering for both hydrogen and oxygen functionalization, is identified. Considering C3N nanoribbons, adsorption of H leads to significant changes in the electronic properties, such as transforming the structures from semiconductor to metallic. Furthermore, investigating the effect of strain on the physical properties, it is found that the band gap can be significantly altered and controlled. The present findings predict that a wide variation in the magnetic and electronic structure of C3N can be achieved by adatom functionalization and conformation indicating its high potential for use in various technological applications, ranging from catalysis, energy storage, and nanoelectronic devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000486528200001 Publication Date 2019-09-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2199-160x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.193 Times cited 35 Open Access  
  Notes ; This work was supported by the FLAG-ERA project 2DTRANS and the Flemish Science Foundation (FWO-Vl). In addition, we acknowledge the OpenMX team for OpenMX code. ; Approved Most recent IF: 4.193  
  Call Number UA @ admin @ c:irua:162790 Serial 5414  
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