E 58 Enyashin, A. N. Mechanical and electronic properties of a C/BN nanocable under tensile deformation [] / A. N. Enyashin, A. L. Ivanovskii // Nanotechnology. - 2005. - V. 16, N 8. - С. 1304-1310. - Bibliogr.: p. 1309-1310 (48 ref.) . - ISSN 0957-4484 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ЭЛЕКТРОННЫЕ СВОЙСТВА -- МЕХАНИЧЕСКИЕ СВОЙСТВА -- СВОЙСТВА ЭЛЕКТРОННЫЕ -- СВОЙСТВА МЕХАНИЧЕСКИЕ -- ДЕФОРМАЦИЯ -- НАПРЯЖЕНИЕ -- КАРБОНОВЫЕ НАНОТРУБКИ -- НАНОТРУБКИ КАРБОНОВЫЕ -- БОРОНИТРИДНЫЕ НАНОТРУБКИ -- НАНОТРУБКИ БОРОНИТРИДНЫЕ Аннотация: Atomistic simulations are performed to investigate the structural, mechanical and electronic properties of a coaxial C/BN nanocable under axial elongation using molecular dynamics. Our results show that the mechanism of the breaking process essentially differs from those for initial single-walled carbon and BN nanotubes. The formation of a carbon as well as a -C-B-N-atomic chain connecting two cable fragments before fracture is obtained, and due to such bridges the cable can be stretched until complete rupture up to epsilon max~29% as compared with epsilon max~23% for a single-walled carbon nanotube. After breakage the opposite tips of cable fragments form different individual atomic morphologies and compositions and can have promising potential as electron emitters. The Young moduli of the C/BN cable and C-NT are comparable. An analysis of the electronic structure shows that during tensile deformation the C/BN cable retains the basic electronic characteristics (metallic-like for the inner carbon nanotube and dielectric for the outer BN tube); however, the bandgap between the highest occupied N 2p and lowest unoccupied B 2p states decreases from 4.0 to 1.2 eV |
E 58 Enyashin, A. N. New nanotubes of metal oxycarbides: Modeling of carbothermal reduction of TiO2 nanotubes [Текст] / A. N. Enyashin, V. G. Bamburov, A. L. Ivanovskii // Doklady Physical Chemistry. - 2006. - Vol. 407, № 1. - С. 57-61. - Библиогр. : с. 61 (15 назв.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Полный текст |
E 58 Enyashin, A. N. Structural, electronic, cohesive, and elastic properties of diamondlike allotropes of crystalline C40 [Текст] / A. N. Enyashin, A. L. Ivanovskii // Physical Review B: Condensed Matter and Materials Physics. - 2008. - Vol. 77, № 11. - С. 113402/1-113402/4. - Библиогр. : с. 113402/4 (21 назв.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): АЛЛОТРОПИЯ -- АЛМАЗОПОДОБНЫЕ КРИСТАЛЛЫ -- ФУЛЛЕРЕНЫ Аннотация: The atomic models of diamondlike allotropes of crystalline C40 hyperdiamond, hyperlonsdaleite and socalled autointercalated hyperdiamond are offered and using the density-functional based tight-binding method their structural, cohesive, elastic, and electronic properties are predicted as well as their theoretical x-ray diffraction spectra are derived. Among these allotropes the autointercalated hyperdiamond C40 has a unique combined type of both covalent and van der Waals bonding and shows the highest density and hardness Полный текст |
E 58 Enyashin, A. N. Atomic and electronic structures and thermal stability of boron-nitrogen nanopeapods: B12N12 fullerenes in BN nanotubes [Текст] / A. N. Enyashin, A. L. Ivanovskii // Physics of the Solid State. - 2008. - Vol. 50, № 2. - С. 390-396. - Библиогр. : с. 396 (26 назв.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): НАНОТРУБКИ -- ФУЛЛЕРЕНЫ -- БОР-АЗОТНЫЕ НАНОТРУБКИ Аннотация: The atomic structures, energies of formation, electronic structures, and thermal stabilities (in the temperature range T= 0–3000 K) of novel hybrid boron–nitrogen nanostructures (so-called nanopeapods B12N12@BN-NT) are simulated using the self-consistent density functional tight-binding (DFTB) method. The B12N12@BN-NT nanopeapods are regular linear ensembles of B 12N12 boron–nitrogen fullerenes encapsulated in boron–nitrogen nanotubes (BN-NT), such as the (14, 0) nonchiral zigzag BN nanotubes, the (8, 8) nonchiral armchair BN nanotubes, and the (12, 4) chiral BN nanotubes Полный текст |
T 80 Toward Atomic-Scale Bright-Field Electron Tomography for the Study of Fullerene-Like Nanostructures [Текст] / M. Bar Sadan, L. Houben, S. G. Wolf, A. N. Enyashin, G. Seifert, R. Tenne, K. Urban // Nano Letters. - 2008. - Vol. 8, № 3. - С. 891-896. - Библиогр. : с. 895 (25 назв.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ФУЛЛЕРЕНЫ -- НАНОСТРУКТУРЫ -- ЭЛЕКТРОННАЯ ТОМОГРАФИЯ Аннотация: We present the advancement of electron tomography for three-dimensional structure reconstruction of fullerene-like particles toward atomicscale resolution. The three-dimensional reconstruction of nested molybdenum disulfide nanooctahedra is achieved by the combination of low voltage operation of the electron microscope with aberration-corrected phase contrast imaging. The method enables the study of defects and irregularities in the three-dimensional structure of individual fullerene-like particles on the scale of 2–3 Å. Control over shape, size, and atomic architecture is a key issue in synthesis and design of functional nanoparticles. Transmission electron microscopy (TEM) is the primary technique to characterize materials down to the atomic level, albeit the images are two-dimensional projections of the studied objects. Recent advancements in aberration-corrected TEM have demonstrated single atom sensitivity for light elements at subångström resolution. Yet, the resolution of tomographic schemes for three-dimensional structure reconstruction has not surpassed 1 nm3, preventing it from becoming a powerful tool for characterization in the physical sciences on the atomic scale. Here we demonstrate that negative spherical aberration imaging at low acceleration voltage enables tomography down to the atomic scale at reduced radiation damage. First experimental data on the three-dimensional reconstruction of nested molybdenum disulfide nanooctahedra is presented. The method is applicable to the analysis of the atomic architecture of a wide range of nanostructures where strong electron channeling is absent, in particular to carbon fullerenes and inorganic fullerenes Полный текст |
E 58 Enyashin, A. N. Prediction of atomic structure and electronic properties of Ti3SiC2 based nanotubes by DFTB theory [Текст] / A. N. Enyashin, A. L. Ivanovskii // Materials Letters. - 2008. - Vol. 62, № 4-5. - С. 663-665 Рубрики: ХИМИЧЕСКИЕ НАУКИ |
E 58 Enyashin, A. N. Structural, thermal properties and stability of monolithic and hollow MgO nanocubes: Atomistic simulation [Текст] / A. N. Enyashin, A. L. Ivanovskii // THEOCHEM. - 2007. - Vol. 822, № 1-3. - С. 28-32 Рубрики: ХИМИЧЕСКИЕ НАУКИ |
T 45 Enyashin, A. N. Electronic, Structural, and Thermal Properties of a Nanocable Consisting of Carbon and BN Nanotubes [Text] / A. N. Enyashin, G. Seifert, A. L. Ivanovskii // JETP Letters. - 2004. - Vol. 80, № 9. - P608-611 : il. - Библиогр. : с. 611 (15 назв.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): НАНОТРУБКИ -- КАРБОН -- НИТРИД БОРА -- СВОЙСТВА ЭЛЕКТРОННЫЕ Аннотация: The band structure and thermal behavior of a coaxial C/BN nanocable (5,5)C@(17,0)BN consisting of a carbon nanotube and a boron nitride nanotube have been studied using a tight-binding approximation based on density functional theory. The system is stable up to T ~ 3500–3700 K. As the temperature increases, deformations of the BN tube begin earlier than those of the carbon tube. The near-Fermi states of the nanocable are formed by the overlapping p–p* bands of the carbon tube, and the outer BN nanotube (the nanocable sheath) is an insulator with a bandgap of ~4 eV. The electronic properties of the nanocable (the metallic-type conductivity of the C tube and the insulating character of the BN tube) are retained over the entire temperature interval \\\\Expert2\\nbo\\JETP Letters\\2004, V.80, N 9, P.608-611.pdf |
I-55 Imogolite Nanotubes: Stability,Electronic, and MechanicalProperties1-3 [Text] / L. Gulmaraes, A. N. Enyashin, J. Frenzel, Th. Heine, H. A. Duarte, G. Seifert // ACS Nano. - 2007. - Vol.1, № 4. - P.362-368 : il. - Bibliogr. : p. 367-368 (38 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): НАНОТРУБКИ -- ПЛОТНОСТЬ ЭЛЕКТРОННАЯ Аннотация: The aluminosilicate mineral imogolite is composed of single-walled nanotubes with stoichiometry of (HO)3Al2O3SiOH and occurs naturally in soils of volcanic origin. In the present work we study the stability and the electronic and mechanical properties of zigzag and armchair imogolite nanotubes using the density-functional tight-binding method. The (12,0) imogolite tube has the highest stability of all tubes studied here. Uniquely for nanotubes, imogolite has a minimum in the strain energy for the optimum structure. This is in agreement with experimental data, as shown by comparison with the simulated X-ray diffraction spectrum. An analysis of the electronic densities of states shows that all imogolite tubes, independent on their chirality and size, are insulators Полный текст |
E 58 Enyashin, A. N. New Self-Intercalated C28, Ti@C28, and Zn@C28Hyperdiamonds: Crystal Structure and Elasticand Electronic Properties [Text] / A. N. Enyashin, A. L. Ivanovskii // JETP Letters. - 2007. - Vol.86, №8. - P.537-542 : ил. - Bibliogr. : p. 541 (26 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): СТРУКТУРА КРИСТАЛЛИЧЕСКАЯ -- ФУЛЛЕРЕНЫ Аннотация: New dense crystal forms of small fullerenes with unusual (combined covalent–van der Waals) atomic bonding, namely, the so-called self-intercalated hyperdiamonds (SIHDs) are suggested. The SIHD systems consist of C28 fullerenes and Ti@C28 and Zn@C28 endofullerenes compacted into diamond lattices, in which the voids are filled with the same fullerenes. The electron density functional method in the tight binding approximation is applied to simulate the structure and to calculate the elasticity parameters, electronic characteristics, and formation energy of C28, Ti@C28, and Zn@C28SIHDs. It is found that the values of the bulk modulus of the SIHDs are much (2.3–2.7 times) greater than those of the initial hyperdiamonds. It is found that the C28 SIHD is a semiconductor with a band gap of about 1.3 eV, whereas the Ti@C 28 and Zn@C28 SIHDs exhibit metal-like electronic spectra. For the alternative diamond-like C28 phases (hyperdiamond, hyperlonsdaleite, and SIHD), the theoretical shape of the x-ray diffraction spectra is calculated Полный текст |
E 58 Enyashin, A. N. DNA-wrapped carbon nanotubes / A. N. Enyashin, S. Gemming, G. Seifert // Nanotechnology. - 2007. - V. 18, № 24. - P. 245702(10 pp.) : il. - Bibliogr. : p. 245702-10(47 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): НАНОТРУБКИ УГЛЕРОДНЫЕ -- ДЕЗОКСИРИБОНУКЛЕИНОВАЯ КИСЛОТА Аннотация: The stability and electronic properties of complexes of single-walled carbon nanotubes wrapped by homopolymeric single-stranded DNA molecules (CNT@DNA) are considered using a quantum mechanical density-functional tight-binding method (DFTB). A phenomenological model of the CNT@DNA formation energy depending on the nanotube radii is developed,which shows that the decoration of a CNT by a few DNA chains leads to a high water solubility of CNT@DNA. Pyrimidine-based DNAs are found to be more effective to wrap the CNTs than other DNAs. The densities of states of the CNT@DNA complexes are close to the superposition of those of the ‘free’ components with some additional states below the Fermi level. The band gap in a hybrid CNT@DNA system is determined by the competition between the Fermi levels of the ‘free’ DNA and CNT. In a few specific cases a considerable charge transfer from the DNA to the CNT was observed, combined with an additional gain in the CNT@DNA formation energy Полный текст |
E 58 Enyashin, A. N. TiSi2 nanostructures – enhanced conductivity at nanoscale? / A. N. Enyashin, S. Gemming // Physica status solidi B. - V. 244, № 10. - P.3593-3600 : il. - Bibliogr. : p. 3599-3600 (30 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): СИЛИЦИД ТИТАНА -- НАНОСТРУКТУРЫ -- НАНОТРУБКИ Аннотация: The structural properties, the stability and the electronic properties of the nanotubes of titanium disilicide are studied using the density-functional-based tight-binding method (DFTB) and compared with ones of the bulk and monolayered TiSi2. These nanotubes were found to be more stable, than a TiSi2 monolayer. All low-dimensional TiSi2 systems are metallic with enhanced densities of Ti 3d-states at the Fermi level Полный текст |
E 58 Enyashin, A. N. Titanium oxide fullerenes: electronic structure and basic trends in theirstability / A. N. Enyashin, G. Seifert // Physical Chemistry Chemical Physics. - 2007. - V. 9, № 43. - P. 5772-5775 : il. - Bibliogr. : p. 5775 (29 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ОКСИД ТИТАНА -- ФУЛЛЕРЕНЫ -- СТРУКТУРА ЭЛЕКТРОННАЯ Аннотация: Stability as a function of size and electronic structure of titania fullerenes, as an example of inorganic fullerenes with octahedral coordination of metal atoms, is studied with the quantum-mechanical DFTB method Полный текст |
E 43 Electronic Structure and Chemical Bonding in Crystalline and Nanosized Forms of Magnesium Diboride / V. G. Bamburov, V. V. Ivanovskaya, A. N. Enyashin, I. R. Shein, N. I. Medvedeva, Yu. N. Makurin, A. L. Ivanovskii // Doklady Physical Chemistry. - 2003. - vol. 388, № 4-6. - P. 43-47 : il. - Bibliogr. : p. 47 (15 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ЭЛЕКТРОННАЯ СТРУКТУРА -- ХИМИЧЕСКИЕ СВЯЗИ -- ДИБОРИД МАГНИЯ -- НАНОРАЗМЕРНЫЕ СТРУКТУРЫ -- СВЕРХПРОВОДИМОСТЬ \\\\Expert2\\nbo\\Doklady Physical Chemistry\\2003, V. 388, N 4-6, p.43-47.pdf |
E 43 Electronic Structure of Doped Titanium Dioxide Nanotubes / A. N. Enyashin, V. V. Ivanovskaya, Yu. N. Makurin, V. G. Bamburov, A. L. Ivanovskii // Doklady Physical Chemistry. - 2003. - vol. 391, № 4-6. - P. 187-190 : il. - Bibliogr. : p. 190 (14 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ЭЛЕКТРОННАЯ СТРУКТУРА -- ДИОКСИД ТИТАНА -- ДОПИРОВАНИЕ -- НАНОТРУБКИ \\\\Expert2\\nbo\\Doklady Physical Chemistry\\2003, V. 391, N 4-6, p.187-190.pdf |
E 43 Electronic Structure of New Graphyne-Like Boron Nitride Nanotubes / A. N. Enyashin, V. V. Ivanovskaya, Yu. N. Makurin, A. L. Ivanovskii // Doklady Physical Chemistry. - 2004. - vol. 395, № 1. - P. 62-66 : il. - Bibliogr. : p. 66 (11 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ЭЛЕКТРОННАЯ СТРУКТУРА -- НИТРИД БОРА -- НАНОТРУБКИ БОРОНИТРИДНЫЕ -- НАНОТРУБКИ ГРАФИНОПОДОБНЫЕ \\\\Expert2\\nbo\\Doklady Physical Chemistry\\2004, V. 395, N 1-3, p. 62-66.pdf |
E 58 Enyashin, A. N. Electronic Structure of Nanotubes of Layered Modifications of Carbon Nitride C3N4 / A. N. Enyashin, A. L. Ivanovskii // Doklady Physical Chemistry. - 2004. - vol. 398, № 1. - P. 211-215 : il. - Bibliogr. : p. Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ЭЛЕКТРОННАЯ СТРУКТУРА -- НАНОТРУБКИ -- НИТРИД УГЛЕРОДА \\\\Expert2\\nbo\\Doklady Physical Chemistry\\2004, V.398, N 1-3, p.211-215.pdf |
E 58 Enyashin, A. N. Coulomb Interactions and the Problem of Stability of Inorganic Nanotubes / A. N. Enyashin, Yu. N. Makurin, A. L. Ivanovskii // Doklady Physical Chemistry. - 2004. - vol. 399, № 2. - P. 293-297 : il. - Bibliogr. : p. 297 (12 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): НЕОРГАНИЧЕСКИЕ НАНОТРУБКИ -- КАРБОНОВЫЕ НАНОТРУБКИ -- МЕТОД КУЛОНОМЕТРИЧЕСКОГО ТИТРОВАНИЯ \\\\Expert2\\nbo\\Doklady Physical Chemistry\\2004, V.399, N 2, p. 293-297.pdf |
I-98 Ivanovskaya, V. V. Structure, Electronic Spectrum, and Chemical Bonding of Fullerene-like Nanoparticles Based on MB2(M = Mg, Al, Sc, Ti) Layered Diborides / V. V. Ivanovskaya, A. N. Enyashin, A. L. Ivanovskii // Inorganic Materials. - 2004. - Vol. 40, № 2. - P. 134-143 : il. - Bibliogr. : p. 141-143 (63 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ФУЛЛЕРЕНОПОДОБНЫЕ НАНОЧАСТИЦЫ -- ДИБОРИДЫ СЛОИСТЫЕ -- ДИБОРИДЫ МЕТАЛЛОВ Аннотация: The structure, electronic spectrum, and interatomic interaction parameters of MnB2n(n= 10, 30, 90, 120, 160; M = Mg, Al, Sc, Ti) fullerene-like molecules based on MB2 layered diborides are assessed using quantum-chemical modeling and are analyzed in relation to the atomic configuration, size, and chemical composition of MnB2n. The electronic structure of concentric nanoparticles consisting of MnB2n cage molecules having identical (M10B20@M90B180) or ifferent (M10B20@ B180, where M, M' = Mg, Al) compositions isconsidered. The results are compared with the electronic properties of crystalline MB2 phases Полный текст |
S 89 Structure and Electronic Spectrum of Fullerene-like Nanoclusters Based on Mo, Nb, Zr, and Sn Disulfides / A. N. Enyashin, V. V. Ivanovskaya, Yu. N. Makurin, A. L. Ivanovskii // Inorganic Materials. - 2004. - Vol. 40, № 4. - P. 395-399 : il. - Bibliogr. : p. 398-399 (21 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): НАНОКЛАСТЕРЫ ФУЛЛЕРЕНОПОДОБНЫЕ -- ДИСУЛЬФИД МОЛИБДЕНА -- ДИСУЛЬФИД НИОБИЯ -- ДИСУЛЬФИД ОЛОВА -- ДИСУЛЬФИД ЦИРКОНИЯ Аннотация: Modeling results are presented on the atomic structure, electronic spectra, and interatomic interaction parameters of quasi-zero-dimensional fullerene-like nanoparticles of Mo, Nb, Zr, and Sn disulfides. These characteristics are analyzed in relation to the chemical composition, size, and atomic configuration of the nanoparticles and are compared to those of nanotubes and crystals of the corresponding disulfides Полный текст |