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Mössbauer spectroscopy of reduced forms of a Fe-tetraphenylporphyrine complex

. Guilard (Eds.), The porphyrin handbook (Vol. 6, pp. 231–256). San Diego: Academic Press. 4. Gurinovich, G. P., Gurinovich, I. F., Ivashin, N. V., Sinyakov, G. N., Shulga, A. M., Terekhov, S. N., Filatov, I. V., & Dziliński, K. (1988). Electronic structure of metalloporphyrin π-anions. J. Mol. Struct. , 172 , 317–343. DOI: 10.1016/0022-2860(88)87026-1. 5. Fukuzumi, S. (2003) Electron transfer chemistry of porphyrins and metalloporphyrins. In K. M. Kadish, K. M. Smith & G. Guilard (Eds.), The porphyrin handbook (Vol. 8, pp. 115–151). Amsterdam: Academic Press

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The Aharonov-Bohm Effect and Transport Properties in Graphene Nanostructures

Abstract

In this paper we discuss interplays between the Aharonov-Bohm effect and the transport properties in mesoscopic ring structures based on graphene. The interlayer interaction leads to a change of the electronic structure of bilayer graphene ring such that the electronic energy dispersion law exhibits a gap, either by doping one of the layers or by the application of an external perpendicular electric field. Gap adjustments can be done by varying the external electric field, which provides the possibility of obtaining mesoscopic devices based on the electronic properties of bilayer graphene. This opens the way to controllable manipulations of phase-coherent mesoscopic phenomena, as well as to Aharonov-Bohm oscillations depending on the height of the potential step and on the radius of the ring. For this purpose one resorts to a tight-binding model such as used to the description of conductance.

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Stability and the Electronic Structure of XB2 (X = Pt, Ir, Pd, Rh, Os) Diborides

. Physical Review Letters, 77, 3865. 18. Monkhorst, H.J., & Pack, J.D. (1976). Special points for Brillouin-zone integrations. Phys. Rev. B, 13, 5188 – 5192. 19. Birch, F. (1947). Finite Elastic Strain of Cubic Crystal. Phys. Rev., 71, 809-824. 20. Staple, C., Mannstadt, W., Asahi, R., & Freeman, A.J. (2001). Electronic structure and physical properties of early transition metal mononitrides: Density-functional theory LDA, GGA, and screened-exchange LDA FLAPW calculations. Phys. Rev. B, 63(15), 155106(1-11). 21. James, A.M. & Lord, M.P. (1992

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Mössbauer study of a tetrakis (pentafluorophenyl) porphyrin iron (III) chloride in comparison with the fluorine unsubstituted analogue

Abstract

Mössbauer investigations, in association with density functional theory (DFT) calculations, have been conducted for the molecular and electronic structures of iron (III) [tetrakis (pentafluorophenyl)] porphyrin chloride [(F20TPP)Fe:Cl], as a Fe(III)-tetraphenylporphyrin complex containing chloride axial ligand and substituted hydrogen atoms by fluorine ones in the four phenyl rings, in comparison with its fluorine unsubstituted analogue [(TPP)Fe:Cl]. It was found that the parameters of Mössbauer spectra of both complexes are close to one another, and correspond to the high-spin state of Fe(III) ions, but they show the different temperature dependence and the quadrupole doublets in Mössbauer spectra show different asymmetry at low temperatures. Results of DFT calculations are analyzed in the light of catalytic activity of the halogenated complex.

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First-Principles Calculations of Oxygen Diffusion in Ti-Al Alloys

Abstract

The projector augmented-wave method within the density functional theory is applied to investigate the oxygen diffusion in the intermetallic Ti-Al alloys. It is shown that the highest oxygen absorption energies in Ti-Al alloys correspond to the octahedral Ti-rich sites but the presence of aluminium in the nearest neighbours leads to a substantial decrease in the oxygen absorption energy in the alloys. The migration barriers for the oxygen diffusion between various interstices in the crystal lattice of the Ti-Al alloys are estimated. The preferred migration paths along a and c axes and limiting barriers of the oxygen diffusion in the alloys are determined. The dependence of the oxygen diffusion coefficient on Ti-Al alloy composition is discussed.

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Computer Simulations of the Band Structure and Density of States of the Linear Chains of NaCl Ions

.A., Becke, D., & Parr, R.G. (1996). Density functional theory of electronic structure. J. Phys. Chem. , 100, 12974–12980. 39. Roessler, D. M., & Walker, W. C. (1968). Electronic spectra of crystalline NaCl and KCl. Physical Review , 166 (3), 599.

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Epr Spectrum Angular Dependences In Liyf4 Crystal / Epr Spektru Leņķiskās Atkarības Liyf4 Kristālā

References 1. Guedes, K.J., Krambrock, K., & Gesland, J.Y. (2002). Identification of trivalent rare earth impurities in YF 3 , LuF 3 and LiYF 4 by electron paramagnetic resonance. Journal of Alloys and Compounds, 344 , 251-254. 2. Yin, J., Zhang, Q., Liu, T., Guo, X., Song, M., Wang, X., & Zhang, H. (2009). Ab initio study of electronic structures of LiYF 4 crystal containing interstitial oxygen atoms. Nuclear Instruments and Methods in Physics Research, B., 267, 74-78. 3. Light, Q.F., & Chen, L

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Study of Copper Nitride Thin Film Structure

prepared by radio-frequency reactive sputtering. J. Appl. Phys. 78 , 4104–4107. DOI: 10.1063/1.359868. 13. Hahn, U., and Weber, W. (1996). Electronic structure and chemical-bonding mechanism of Cu 3 N, Cu 3 NPd, and related Cu(I) compounds. Phys. Rev. B 53 , 12684. DOI: 10.1103/PhysRevB.53.12684. 14. Moreno-Armenta, M.G., Martínez-Ruiz, A., and Takeuchi, N. (2004). Ab initio total energy calculations of copper nitride: The effect of lattice parameters and Cu content in the electronic properties. Solid State Sci. 6, 9–14. DOI: 10.1016/j

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STUDY OF SUPERCONDUCTING EFFECTS IN TRANSITION METALS BASED BINARY ALLOYS USING PSEUDOPOTENTIAL THEORY

). Transition temperature of strong-coupled superconductors. Phys. Rev., 167 (2), 331-344. DOI: 10.1103/PhysRev.167.331. Ashcroft, N. W. (1968). Electron-ion pseudopotentials in the alkali metals. J. Phys., C1 (1), 232-243. DOI: 10.1088/0022-3719/1/1/3260. Harrison, W. A. (1999). Elementary Electronic Structure. Singapore: World Scientific. Taylor R. (1978). A simple, useful analytical form of the static electron gas dielectric function, J. Phys. F: Met. Phys. 8 (8), 1699-1702. DOI: 10

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Luminescence Properties and Decay Kinetics of Mn2+ and Eu3+ Co-Dopant Ions In MgGa2O4 Ceramics

–1256. 6. Porotnikova, N. M., Eremin, V. A., Farlenkov, A. S., Kurumchin, E. K., Sherstobitova, E. A., Kochubey, D. I., & Ananyev, M. V. (2018). Effect of AO segregation on catalytical activity of La 0.7 A 0.3 MnO 3±δ (A= Ca, Sr, Ba) regarding oxygen reduction reaction. Catalysis Letters , 148 (9), 2839–2847. 7. Piskunov, S., Isakoviča, I., & Popov, A. I. (2018). Electronic structure of Mn 3+ Al and Mn 2+ Al- doped YAlO 3 : Prediction from the first principles. Optical Materials , 85 , 162–166. 8. Klym, H., Ingram, A., Shpotyuk, O., Hadzaman, I

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