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Djaafri A, Kadoun AED, Driss-Khodja M. Study of Defects Produced by Displacement Cascades in Tantalum Monocarbide. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2018. [DOI: 10.1007/s13369-018-3127-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Owolabi TO, Akande KO, Olatunji SO. Estimation of average surface energies of transition metal nitrides using computational intelligence technique. Soft comput 2016. [DOI: 10.1007/s00500-016-2174-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Wang S, Du YL, Li JX, Ou YY, Cui C. Phase stability and elastic properties of graphene-like Tan+1Cn (n = 1, 2, or 3) from first-principles calculations. ACTA ACUST UNITED AC 2015. [DOI: 10.1179/1432891715z.0000000001558] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Affiliation(s)
- S. Wang
- School of Materials Science and Engineering Nanjing University of Science and Technology, Nanjing 210094, China
| | - Y. L. Du
- School of Mechanical Engineering Nanjing University of Science and Technology, Nanjing 210094, China
| | - J. X. Li
- School of Materials Science and Engineering Nanjing University of Science and Technology, Nanjing 210094, China
| | - Y. Y. Ou
- College of Elite Education Nanjing University of Science and Technology, Nanjing 210094, China
| | - C. Cui
- School of Materials Science and Engineering Nanjing University of Science and Technology, Nanjing 210094, China
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Kang DB. Effect of Valence Electron Concentration on Elastic Properties of 4d Transition Metal Carbides MC (M = Y, Zr, Nb, and Rh). B KOREAN CHEM SOC 2013. [DOI: 10.5012/bkcs.2013.34.7.2171] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Tütüncü HM, Baǧcı S, Srivastava GP, Akbulut A. Electrons, phonons and superconductivity in rocksalt and tungsten-carbide phases of CrC. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:455704. [PMID: 23092975 DOI: 10.1088/0953-8984/24/45/455704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We present results of ab initio theoretical investigations of the electronic structure, phonon dispersion relations, electron-phonon interaction and superconductivity in the rocksalt and tungsten-carbide phases of CrC. It is found that, compared to the stable tungsten-carbide phase, the metastable rocksalt phase is characterized by a much larger electronic density of states at the Fermi level. The phonon spectra of the rocksalt phase exhibit anomalies in the dispersion curves of both the transverse and longitudinal acoustic branches along the main symmetry directions. A combination of these characteristic electronic and phonon properties leads to an order of magnitude larger value of the electron-phonon coupling constant (λ = 2.66) for the rocksalt phase compared to that for the tungsten-carbide phase (λ = 0.24). Our calculations suggest that superconducting transition temperature values of 0.01 K and 25-35 K may be expected for the tungsten-carbide and rocksalt phases, respectively.
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Affiliation(s)
- H M Tütüncü
- Sakarya Üniversitesi, Fen-Edebiyat Fakültesi, Fizik Bölümü, 54187, Adapazarı, Turkey.
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Farhat A, Korek M, Marques M, Abdul-Al S. Ab initio calculation of the low-lying electronic states of the ZrN molecule. CAN J CHEM 2012. [DOI: 10.1139/v2012-036] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
An ab initio calculation of the low-lying electronic states of zirconium nitride (ZrN) were performed by using a complete active space self-consistent field with multireference single and double excitation configuration interaction (MRSDCI). The potential energy curves of 21 low-lying electronic states of the ZrN molecule with different spin and spatial symmetries, in the representation 2s+1Λ(+/−) and below 30 000 cm–1, were identified. The harmonic frequency (ωe), the equilibrium internuclear distance (Re), the rotational constants (Be), the electronic energy with respect to the ground state (Te), and the permanent dipole moment (µ) were calculated for the considered electronic states. The comparison of these values with those available in the literature shows a very good agreement with either theoretical or experimental data. Fifteen new electronic states were studied here for the first time.
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Affiliation(s)
- A. Farhat
- Université de Lyon, F-69000 Lyon, France and LPMCN, CNRS, UMR 5586, Université Lyon 1, F-69622 Villeurbanne, France
| | - M. Korek
- Faculty of Science, Beirut Arab University, P.O. Box 11-5020 Riad El Solh, Beirut 1107 2809, Lebanon
| | - M.A.L. Marques
- Université de Lyon, F-69000 Lyon, France and LPMCN, CNRS, UMR 5586, Université Lyon 1, F-69622 Villeurbanne, France
| | - S.N. Abdul-Al
- Faculty of Science, Lebanese International University, Museitbeh, Beirut, Lebanon
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Vojvodic A, Ruberto C. Trends in bulk electron-structural features of rocksalt early transition-metal carbides. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:375501. [PMID: 21403197 DOI: 10.1088/0953-8984/22/37/375501] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A detailed and systematic density-functional theory (DFT) study of a series of early transition-metal carbides (TMCs) in the NaCl structure is presented. The focus is on the trends in the electronic structure and nature of bonding, which are essential for the understanding of the reactivity of TMCs. The employed approach is based on a thorough complementary analysis of the electron density differences, the density of states (DOS), the band structure and the real-space wavefunctions to gain an insight into the bonding of this class of materials and get a more detailed picture of it than previously achieved, as the trend study allows for a systematic identification of the bond character along the different bands. Our approach confirms the presence of both the well-known TM-C and TM-TM bonds and, more importantly, it shows the existence and significance of direct C-C bonds in all investigated TMCs, which are frequently neglected but have been identified in some cases (Zhang et al 2002 Solid State Commun. 121 411; Ruberto et al 2007 Phys. Rev. B 75 235438). New information on the spatial extent of the bonds, their k-space location within the band structure and their importance for the bulk cohesion is provided. Trends in covalency and ionicity are presented. The resulting electron-structural trends are analyzed and discussed within a two-level model.
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Affiliation(s)
- Aleksandra Vojvodic
- Department of Applied Physics, Chalmers University of Technology, Göteborg, Sweden.
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Jun-Qian L, Yong-Fan Z. A density functional study on the electronic structures of TiN solid. CHINESE J CHEM 2010. [DOI: 10.1002/cjoc.20000180306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Wolf W, Podloucky R, Antretter T, Fischer FD. First-principles study of elastic and thermal properties of refractory carbides and nitrides. ACTA ACUST UNITED AC 2009. [DOI: 10.1080/13642819908214844] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- W. Wolf
- a Institute for Physical Chemistry, University of Vienna , Liechtensteinstrasse 22A, A-1090, Vienna , Austria
- c Molecular Simulations, Parc Club Orsay Université , 20, rue Jean Rostand, 91893, Orsay , Cedex , France
| | - R. Podloucky
- a Institute for Physical Chemistry, University of Vienna , Liechtensteinstrasse 22A, A-1090, Vienna , Austria
| | - T. Antretter
- b Institute for Mechanics, University of Mining , A-8700 Leoben, Austria
| | - F. D. Fischer
- b Institute for Mechanics, University of Mining , A-8700 Leoben, Austria
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Electronic and mechanical properties of 5d transition metal mononitrides via first principles. J SOLID STATE CHEM 2008. [DOI: 10.1016/j.jssc.2008.07.022] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Verma AS, Bhardwaj SR. Correlation between ionic charge and ground-state properties in rocksalt and zinc blende structured solids. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2006; 18:8603-8612. [PMID: 21690912 DOI: 10.1088/0953-8984/18/37/018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In this paper we have evaluated the ground-state properties (i.e., bulk modulus and cohesive energy) of rocksalt and zinc blende structured solids. We have presented two expressions relating the bulk modulus B (GPa) for the alkali halides, alkaline-earth chalcogenides, transition metal nitrides, rare-earth {divalent (R(2+)X) and trivalent (R(3+)X) } monochalcogenides, group IV, III-V and II-VI semiconductors and the cohesive energy E(coh) (kcal mol(-1)) for the alkali halides and alkaline-earth chalcogenides with the product of ionic charges (Z(1)Z(2)) and nearest-neighbour distance d (Å). The bulk moduli and cohesive energy of rocksalt and zinc blende type structure compounds exhibit a linear relationship when plotted on a log-log scale against the nearest-neighbour distance d (Å), but fall on different straight lines according to the ionic charge product of the compounds. We have applied the modified relation on rocksalt and zinc blende structured solids and found a better agreement with experimental data as compared to the values evaluated by earlier researchers. The results for bulk modulus differ from experimental values by the following amounts: BaO-0%, LiCl-0%, LaS-0%, SmSe-0%, ZnS-0%, CdS-0%, GaP-0%, InP-0%, MgO-0.61%, CaO-0.89%, SmS-1.7%, YbSe-1.6%, UP-1.9%, EuSe-1.9%; and the results for cohesive energy differ from experimental values by the following amounts: LiCl-0.49%, KF-0.51%, RbF-0.54%, SrO-1.2%, NaCl-1.6%, NaF-1.8%, MgSe-1.9%.
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Affiliation(s)
- A S Verma
- Department of Physics, BSA College Mathura, 281004, India
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Viñes F, Sousa C, Liu P, Rodriguez JA, Illas F. A systematic density functional theory study of the electronic structure of bulk and (001) surface of transition-metals carbides. J Chem Phys 2005; 122:174709. [PMID: 15910062 DOI: 10.1063/1.1888370] [Citation(s) in RCA: 161] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
A systematic study of the bulk and surface geometrical and electronic properties of a series of transition-metal carbides (TMC with TM = Ti, V, Zr, Nb, Mo, Hf, Ta, and W) by first-principles methods is presented. It is shown that in these materials the chemical bonding is strongly covalent, the cohesive energies being directly related to the bonding-antibonding gap although the shift of the center of the C(2s) band related peak in the density of states with respect to diamond indicates that some metal to carbon charge transfer does also take place. The (001) face of these metal carbides exhibits a noticeable surface rumpling which grows along the series. It is shown that neglecting surface relaxation results in very large errors on the surface energy and work function. The surface formation induces a significant shift of electronic energy levels with respect to the corresponding values in the bulk. The extent and nature of the shift can be understood from simple bonding-antibonding arguments and is enhanced by the structural rippling of this surface.
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Affiliation(s)
- F Viñes
- Departament de Química Física & Centre especial de Recerca en Química Teòrica, Universitat de Barcelona & Parc Científic de Barcelona, Spain
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A density functional study on the electronic structures of TiX (X=C, N, O). Part I. The electronic structures and bonding properties of TiN bulk and (001) surface. ACTA ACUST UNITED AC 2000. [DOI: 10.1016/s0166-1280(00)00337-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Häglund J, Fernández Guillermet A, Grimvall G, Körling M. Theory of bonding in transition-metal carbides and nitrides. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 48:11685-11691. [PMID: 10007503 DOI: 10.1103/physrevb.48.11685] [Citation(s) in RCA: 113] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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