Annual Report 2012 - Latvijas Universitātes Cietvielu fizikas institūts

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correlation functionals (PBE and PBE0, respectively), using the formalism of linear combination of localized atomic functions (LCAO) implemented in CRYSTAL09 code. Both structural and electronic properties of enumerated rutile-based titania slabs and nanowires have been calculated. ` a) (110) d [001] 0) b) l [001] Fig. 8. Cross sectional (a) and lateral (b) images of non-optimized large rutile-based [001]-oriented Ti atom-centered nanowire possessing the D 2h symmetry and containing 81 formula units per NW unit cell with aside (110) and ( ) facets shown in Fig. 8b. Red rhombs in Fig. 8a show borders for prism models of middle, small and smallest TiO 2 NWs (49, 25 and 9 formula units per UC, respectively). Diameter of a nanowire is shown by the twice-terminated arrow (d [001] ) while its period (length of UC) is shown in Fig. 8.b as l [001] . Nanowires are constructed as 1D systems cut from the 3D crystal along the direction of one of the bulk crystal symmetry axes. The translational periodicity is maintained along this direction. In the case of a rutile-based [001] TiO 2 nanowire (Fig. 8) a direction of the translation axis is orthogonal to a pair of [110] and [ ] vectors while both titania formula units of primitive cell lie in the two cross-sectional planes. If the translational two-fold rotation axis goes through a Ti atom (Fig. 8), one can see that the reflection in the horizontal (h) plane and rotations around the two second order axes in this plane are the symmetry operations for [001]-oriented nanowires. The rod symmetry group of this system is Pmmm while its point symmetry group is D 2h . For a rutile-based [110] nanowire (Fig. 9), the translation axis is orthogonal to [001] and [ ] vectors while four formula units of primitive cell lie in the six cross-sectional planes. The symmetry of a rutile-based [110] nanowire coincides with the symmetry of analogous type of [001] NW if the translation axis with rotation by π goes through Ti atoms. Indeed, Fig. 9, shows that the symmetry operations for [110] NWs are reflection in the vertical (v) plane (containing the translation axis) and rotation around the 2-fold translation axis in this plane. The symmetry operations include also rotations around the 2-fold axis in the horizontal (h) plane (orthogonal to the translation axis). Thus, the rod symmetry group of the system is again Pmmm (the point symmetry group is D 2h ). 62
a) b) l [110] d [110] (001) Fig. 9. Cross sectional (a) and lateral (b) images of the non-optimized large rutile-based [110]-oriented Ti atom-centered NW possessing the D 2h symmetry and containing 105 formula units per NW UC, with aside (001) and ( ) facets (the former is shown in Fig. 9.b). Rectangles in Fig. 9.a show borders for prism models of middle, small and smallest TiO 2 NWs (55, 21 and 3 formula units per UC, respectively). NW diameter is shown by the twice-terminated arrow (d [110] ) while its period (length of UC) is shown in Fig. 9.b as l [110] . The properties of titania nanowires are both the size and shape dependent. For direct comparison of relative stability of various 1D nanowires, we have performed large-scale calculations on their surface energy per formula unit. Values of d NW slightly increase whereas l NW are found to be reduced after NW geometry optimization. The larger is d NW , the closer its geometry parameters as well as the band gap to those of rutile-based TiO 2 bulk and non-optimized (001) and (110) slabs whereas NW surface energy approaches to that of facets terminating the nanowire. In the case of Ti atom-centered NWs, values of Δε g grow with increasing d NW while in hollow site-centered NWs, these values decrease in analogous conditions, analogously to band gaps of slabs with increasing thickness. THEORETICAL SIMULATIONS OF ELECTROMAGNTIC PROPERTIES IN CARBON NNTUBES AND GRAPHENE BASED NANOSTRUCTURES Yu.N. Shunin, Yu.F. Zhukovskii, S. Bellucci (Laboratori Nazionali di Frascati, Italy) In collaboration with Dr. S. Bellucci (Laboratori Nazionali di Frascati, Italy), we have developed the model of ‘effective bonds’ in the framework of both cluster approach based on the multiple scattering theory formalism and Landauer theory, which can allow us to predict the resistivity properties for C-Me junctions taking into account chirality effects in the interconnects of single-wall (SW) and multi-wall (MW) CNTs (Fig. 10) as well as monolayer (ML) and polylayer (PL) GNRs (Fig. 11) with the fitting metals (Me= Ni, Cu, Ag, Pd, Pt, Au) on predefined geometry of carbon nanostructure. 63
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Institute of Solid State Physics Un
Page 3 and 4:
CONTENTS Introduction 4 Department
Page 5 and 6:
ORGANIZATIONAL STUCTURE OF THE ISSP
Page 7 and 8:
The annual report summarizes the re
Page 9 and 10:
The main source for international f
Page 11 and 12: lector at the Faculty of Physics an
Page 13 and 14: the samples having different phase
Page 15 and 16: LABORATORY OF MAGNETIC RESONANCE SP
Page 17 and 18: Scientific publications 1. U. Rogul
Page 19 and 20: Main investigations and results ALU
Page 21 and 22: Lectures on Conferences 28 th LU Sc
Page 23 and 24: Main Results LASER CRYSTALLIZATION
Page 25 and 26: CONTROLLED MANIPULATION AND MECHANI
Page 27 and 28: DEPARTMENT OF FERROELECTRICS Head o
Page 29 and 30: Belorussia 1. Institute of solid st
Page 31 and 32: Density and dielectric properties f
Page 33 and 34: CONCENTRATION AND THERMAL PHASE TRA
Page 35 and 36: Latvia; SSPA ”Scientific-Practica
Page 37 and 38: • Δ T εmax : Mn>Co>Fe>Cu~Ni •
Page 39 and 40: Li x Na 1-x Ta y Nb 1-y O 3 Solid S
Page 41 and 42: 34. А.И. Бурханов, И.Е.
Page 43 and 44: 16. Š. Svirskas, M. Ivanov, Š. Ba
Page 45 and 46: 45. С.Н. Каллаев, А.Р.
Page 47 and 48: LABORATORY OF VISUAL PERCEPTION Hea
Page 49 and 50: in terms of colour coordinate dispe
Page 51 and 52: 4. R.Truksa, S.Fomins, M.Ozolins, "
Page 53 and 54: Scientific visits abroad 1. Dr. hab
Page 55 and 56: experimental data. We focused on th
Page 57 and 58: GB1 with oxygen vacancy revealed th
Page 59 and 60: Fig. 4. The thermodynamic stability
Page 61: a supercell model was used, and the
Page 65 and 66: Drain CNT Source Drain GNR Source 5
Page 67 and 68: The oxygen incorporation energy for
Page 69 and 70: such as high thermal stability, ver
Page 71 and 72: STATISTICAL ANALYSIS AND CELLULAR A
Page 73 and 74: REGIONS OF AZIMUTHAL INSTABILITY IN
Page 75 and 76: 25. A. Gopejenko, Yu.F. Zhukovskii,
Page 77 and 78: 15. S. Piskunov and E. Spohr, "SrTi
Page 79 and 80: 43. P. Merzlakov, G. Zvejnieks, V.N
Page 81 and 82: XII. Annual Monitory Meeting of Eur
Page 83 and 84: 91. L. Shirmane, A.I. Popov, V. Pan
Page 85 and 86: 115. A.I. Popov, J. Zimmermann, V.
Page 87 and 88: Estonia Institute of Physics, Tartu
Page 89 and 90: 5. Grigorjeva L., Jankoviča D., Sm
Page 91 and 92: LABORATORY OF AMORPHOUS MATERIALS S
Page 93 and 94: Main results ABSORPTION AND LUMINES
Page 95 and 96: LUMINESCENCE OF FUSED AND UNFUSED B
Page 97 and 98: enables sensitive and selective det
Page 99 and 100: LABORATORY OF OPTICAL RECORDING Hea
Page 101 and 102: HOLOGRAPHIC LITHOGRAPHY IN AMORPHOU
Page 103 and 104: 5. U.Gertners, J.Teteris, The impac
Page 105 and 106: 24. J.Aleksejeva, J.Teteris, A.Tokm
Page 107 and 108: Israel Technion, Haifa (Dr.S.Stolya
Page 109 and 110: 3. A. Rusakova, J. Maniks, K. Schwa
Page 111 and 112: • Investigation of energetic stru
Page 113 and 114:
Scheme 2 Synthesis of indane-1,3-di
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The synthesized compounds ZWK-1, DW
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7. A. Vembris, K. Pudzs, I. Muzikan
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20. A. Vembris, K. Pudzs, I. Muzika
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• Ion transfer problems related t
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13. SIA „EMU PRIM”, 14. JSC „
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Main results Laboratory of Solid St
Page 127 and 128:
Flax and Hemp Fiber Functionalizati
Page 129 and 130:
CHARACTERIZATION OF LiFePO4/C COMPO
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Fig.1. Upper panel: 4 × 4 ×4 supe
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Fig.1. Left panel: Schematic view o
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Titania with anatase structure is i
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RESEARCH OF CATHODE MATERIALS FOR L
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17. T Dizhbite, J Ponomarenko, A An
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6. J. Kleperis, B. Sloka, J. Dimant
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33. P. Lesnicenoks, A. Sivars, L. G
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France 1. Institute Laue-Langevin,
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different neutron orbits (11/2[615]
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LABORATORY OF ELECTRONIC ENGINEERIN
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2. For JSC Augstsprieguma tīkls an
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4. By orders of several organizatio
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Partners: Fonons Ltd, Riga Technica
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Annual Report 2012 - Latvijas Universitātes Cietvielu fizikas institūts

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