S 53 Shein, I. R. Elastic properties of carbide, nitride, and boride ceramics with WC-type structures [Текст] / I. R. Shein, D. V. Suetin, A. L. Ivanovskii // Technical Physics Letters. - 2008. - Vol. 34, № 10. - С. 841-844. - Библиогр. : с. 844 (15 назв.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: The elastic constants (Cij) of boride, carbide, and nitride (RuB, WC, WN, and TaN) ceramics with WC-type structures have been calculated using the full-potential linearized augmented plane wave (FLAPW) method with an exchange-correlation potential in the generalized gradient approximation (GGA). Numerical estimates of elastic parameters of the corresponding polycrystalline ceramics (bulk compression modulus, shear modulus, Youngis modulus, Poissonis ratio, and Lameis coefficients) of these ceramics are obtained and analyzed for the first time. Полный текст |
S 91 Suetin, D. V. Structural,electronic properties and stability of tungsten mono- and semi-carbides:A first principles investigation / D. V. Suetin, I. R. Shein, A. L. Ivanovskii // Journal of Physics and Chemistry of Solids. - 2009. - Vol. 70. - P. 64-71 : il. - Bibliogr. : p. 70-71 (49 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): НЕОРГАНИЧЕСКИЕ СОЕДИНЕНИЯ -- РАСЧЕТЫ -- СТРУКТУРА КРИСТАЛЛИЧЕСКАЯ -- СТРУКТУРА ЭЛЕКТРОННАЯ -- ТЕРМОДИНАМИКА Аннотация: First principles calculations have been performed with the purpose to understand the comparative peculiarities of the structural, electronic properties and stability for all phases formed in the tungsten–carbon system:hexagonal and cubic mono-carbides WC and four polymorphs(a, b, g and e) of semi-carbideW2C. All calculations were performed by means of the full-potential linearized augmented plane wave method FLAPW). The generalized gradient approximation(GGA)in the Perdew–Burke–Ernzerhof(PBE) formalism was used for the exchange and correlation energy functional. The geometries of all WC and W2C phases were optimized and their structural parameters and theoretical density were established. Besides,we have evaluated the formation energies(Eform) of all the tungsten carbides.Based on our estimations we can arrange all investigated W–C phases depending on??their stability in the following sequence: h-WC4e-W2C4b-W2C4g-W2C4a-W2C4c-WC.Here three carbides(h-WC, e-W2C and b-W2C) are stable(Eformo0), g-W2C belongs to metastable systems (Eform<0), whereas a-W2C and c-WC appear to be unstable(Eform40). Moreover,band structures, total and partial densities of states were obtained and analyzedsystematically for all W–C phases in comparison with other availablet heoretical and experimental data Полный текст |
S 91 Suetin, D. V. Structural, elastic and electronic properties and formation energiesfor hexagonal (W0.5Al0.5)C in comparison with binary carbidesWC and Al4C3 from first-principles calculations / D. V. Suetin, I. R. Shein, A. L. Ivanovskii // Physica B. - 2008. - Vol. 403. - P. 2654-2661 : il. - Bibliogr. : p. 2660-2661 (41 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): РАСЧЕТЫ ПЕРВОПРИНЦИПНЫЕ -- КАРБИДЫ -- W-Al-C -- СВОЙСТВА УПРУГИЕ -- СВОЙСТВА СТРУКТУРНЫЕ -- СВОЙСТВА ЭЛЕКТРОННЫЕ Аннотация: First principle calculations have been performed with the purpose to understand the peculiarities of the structural, elastic parameters and electronic properties and interatomic bonding for novel hexagonal carbide (W0.5Al0.5)C in comparison with binary phases WC and Al4C3. The geometries of all phases were optimized and their structural, elastic parameters and theoretical density were established. Besides, we have evaluated the formation energies (Eform) of W0.5Al0.5C for different possible preparation routes (namely for the reactions with the participation of simple substances (metallic W, Al and graphite, binary W or Al carbides and metallic Al and W, or binary W and Al carbides). The results show that the synthesis of the ternary carbide from simple substances is more favorable in comparison with the reactions with participation of W and Al carbides. Moreover, band structures, total and partial densities of states were obtained and analyzed systematically for (W0.5Al0.5)C, WC and Al4C3 phases in comparison with available theoretical and experimental data. The bonding picture in W0.5Al0.5C was described as a mixture of metallic, ionic and covalent contributions with the high anisotropy for the covalent W–C and Al–C bonds, where p–p like Al–C bonds become weaker than p–d like W–C bonds Полный текст |
S 91 Suetin, D. V. Electronic properties of the hexagonal tungsten monocarbide(h-WC) with 3d impurities from first-principles calculations / D. V. Suetin, I. R. Shein, A. L. Ivanovskii // Physica B. - 2009. - Vol. 404. - P. 1887-1891 : il. - Bibliogr. : p. 1891 (24 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): КАРБИД ВОЛЬФРАМА -- РАСЧЕТЫ ПЕРВОПРИНЦИПНЫЕ -- СВОЙСТВА ЭЛЕКТРОННЫЕ -- СВОЙСТВА СТРУКТУРНЫЕ -- СВОЙСТВА МАГНИТНЫЕ Аннотация: First-principles FLAPW-GGA calculations have been performed to predict the structural, electronic, cohesive and magnetic properties for hexagonal tungsten monocarbide (h-WC) doped with all 3d metals.The optimized lattice parameters, density of states, cohesive and formation energies have been obtained and analyzed for ternary solid solutions with nominal compositions W0.875M0.125C (where M = Sc, Ti ...Ni, Cu). In addition, the magnetic properties of these solid solutions have been examined, and magnetization has been established for W0.875Co0.125C Полный текст |
I-60 Influence of Carbon Vacancies on the Electronic Properties of Solid Solutions in the W–Al–C System from First Principles Calculations / D. V. Suetin, I. R. Shein, V. G. Bamburov, A. L. Ivanovskii // Doklady Physical Chemistry. - 2009. - vol. 424, № 1. - P. 14-16 : il. - Bibliogr. : p. 16 (13 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ЭЛЕКТРОННЫЕ СВОЙСТВА -- РАСТВОРЫ ТВЕРДЫЕ -- РАСЧЕТЫ ПЕРВОПРИНЦИПНЫЕ -- КАРБИДЫ ПЕРЕХОДНЫХ МЕТАЛЛОВ \\\\Expert2\\nbo\\Doklady Physical Chemistry\\2009, V. 424, N 1, p.14-16.pdf |
B 22 Band Structure and Properties of Polymorphic Modifications of Lower Tungsten Carbide W2C / D. V. Suetin, I. R. Shein, A. S. Kurlov, A. I. Gusev, A. L. Ivanovskii // Physics of the Solid State. - 2008. - Vol. 50, № 8. - P1420-1426 : il. - Bibliogr. : p. 1426 (20 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): КАРБИД ВОЛЬФРАМА -- ПОЛИМОРФНЫЕ МОДИФИКАЦИИ Аннотация: The structural and electronic properties are investigated and the relative stabilities of all the known polymorphic modifications (α,β,γ,ε) of the lower tungsten carbide W2C are numerically estimated using the ab initio full-potential linearized augmented plane wave (FLAPW) method within the generalized gradient approximation (GGA) of the local spin density. The equilibrium parameters of the crystal lattices, the band structures, and the total and partial densities of states are determined for the first time within a unified approach. The energies of formation of the α,β,γ, and ε polymorphic modifications of the lower tungsten carbide [in the reactions W2C<-> 2W + C (graphite)] are calculated and used to discuss their relative stabilities Полный текст |
S 91 Suetin, D. V. Structural and electronic properties of eight ternary semiconducting acetylides A2MC2 (where A=Na, K, Rb, and Cs; M=Pd and Pt) as obtained from first-principles calculations / D. V. Suetin, A. L. Ivanovskii // Materials Science in Semiconductor Processing. - 2014. - Vol. 19. - P72-77 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ПАЛЛАДИЙ -- ПЛАТИНА -- ЭЛЕКТРОННЫЕ СВОЙСТВА Аннотация: By means of the first-principle calculations, we have systematically investigated the structural and electronic properties of a complete series of known ternary palladium and platinum acetylides: Na2PdC2, K2PdC2, Rb2PdC2, Cs2PdC2, Na2PtC2, K2PtC2, Rb2PtC2, and Cs2PtC2. Our results cover the optimized lattice parameters, inter-atomic distances, formation and cohesive energies, as well as electronic bands, total and atomic-resolved l-projected densities of electronic states (DOSs), which are discussed in comparison with available experimental and theoretical data. |