A Tight Binding Model for The Electronic Structure of FCC and SC C60

Ab-initio calculations1 for K3C60 indicate that the general features of the energy bands within LDA remain nearly unchanged as compared to C60. In the electronphonon pairing mechanism of superconductivity in these materials, the variation in Tc has been attributed to changes in the lattice constant2 which affects N(EF). We have therefore fitted the valence and conduction bands of the fcc C60, obtained by Troullier and Martins3 from an LDA plane wave basis calculations, with a tight binding model and studied the energy bands as a function of the lattice constant. As the overlap between orbitals on neighbouring balls is small, the band width is found to decrease by about 30% in going from K3C60 to Rb2CsC60. The density of states, thus, obtained is used to estimate variation in Tc from McMillan’s formula. These results are in good agreement with experimental data. Calculations of the energy bands are also presented for the low temperature [Formula: see text] structure.

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Comparison between Monolayer and Bilayer Graphene energy bands using the Tight Binding model

Journal of Physics Conference Series ◽

10.1088/1742-6596/1143/1/012022 ◽

2018 ◽

Vol 1143 ◽

pp. 012022

Author(s):

Lucila Menacho ◽

M. Carrasco ◽

Z. Ayala

Keyword(s):

Tight Binding ◽

Bilayer Graphene ◽

Tight Binding Model ◽

Energy Bands ◽

Binding Model

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Energy bands in graphene: Comparison between the tight-binding model andab initiocalculations

Physical Review B ◽

10.1103/physrevb.89.165430 ◽

2014 ◽

Vol 89 (16) ◽

Cited By ~ 26

Author(s):

E. Kogan ◽

V. U. Nazarov ◽

V. M. Silkin ◽

M. Kaveh

Keyword(s):

Tight Binding ◽

Tight Binding Model ◽

Energy Bands ◽

Binding Model

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Tight-binding model for the energy bands in solids

Chemical Physics Letters ◽

10.1016/0009-2614(69)80111-9 ◽

1969 ◽

Vol 3 (3) ◽

pp. 119-121 ◽

Cited By ~ 5

Author(s):

Jan Linderberg ◽

Yngve Öhrn

Keyword(s):

Tight Binding ◽

Tight Binding Model ◽

Energy Bands ◽

Binding Model

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Composition and Strain Dependence of the Piezoelectric Coefficients in Semiconductor Alloys

MRS Proceedings ◽

10.1557/proc-1017-dd04-11 ◽

2007 ◽

Vol 1017 ◽

Author(s):

T. Hammerschmidt ◽

M. A. Migliorato ◽

D. Powell ◽

A. G. Cullis ◽

G. P. Srivastava

Keyword(s):

First Principles ◽

Density Functional ◽

Piezoelectric Coefficient ◽

Tight Binding ◽

Tight Binding Model ◽

Semiconductor Alloys ◽

Binding Model ◽

Functional Theory ◽

Photo Current ◽

Good Agreement

AbstractWe propose a tight-binding model for the polarization that considers direct and dipole contributions and employs microscopic quantities that can be calculated by first-principles methods, e.g. by employing Density Functional Theory (DFT). Applying our model to InxGa1-xAs alloys allows us to settle discrepancies between the values of e14 as obtained from experiments and from linear interpolations between the values of InAs and GaAs. Our calculated piezoelectric coefficient is in very good agreement with photo current measurements of InAs/GaAs(111) quantum well samples.

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A Tight-Binding Model for Optical Properties of Porous Silicon

MRS Proceedings ◽

10.1557/proc-491-365 ◽

1997 ◽

Vol 491 ◽

Author(s):

M. Cruz ◽

M. R. Beltran ◽

C. Wang ◽

J. Tagüeña-Martinez

Keyword(s):

Optical Properties ◽

Porous Silicon ◽

Crystalline Silicon ◽

Tight Binding ◽

Basis Set ◽

Extended Defects ◽

Tight Binding Model ◽

Binding Model ◽

Semi Empirical ◽

Good Agreement

ABSTRACTSemi-empirical tight-binding techniques have been extensively used during the last six decades to study local and extended defects as well as aperiodic systems. In this work we propose a tight-binding model capable of describing optical properties of disordered porous materials in a novel way. Besides discussing the details of this approach, we apply it to study porous silicon (p-Si). For this purpose, we use an sp3s* basis set and supercells, where empty columns are digged in the [001] direction in crystalline silicon (c-Si). The disorder of the pores is considered through a random perturbative potential, which relaxes the wave vector selection rule, resulting in a significant enlargement of the optically active k-zone. The dielectric function and the light absorption spectra are calculated. The results are compared with experimental data showing a good agreement.

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Spin-Polarization in Ultrathin Rh Layers on Fe (001)

MRS Proceedings ◽

10.1557/proc-313-595 ◽

1993 ◽

Vol 313 ◽

Author(s):

A. Chouairi ◽

H. Dreysse ◽

H. Nait-Laziz ◽

C. Demangeat

Keyword(s):

Spin Polarization ◽

Photoelectron Spectroscopy ◽

Tight Binding ◽

Mean Field ◽

Lattice Parameter ◽

Tight Binding Model ◽

Binding Model ◽

Fee Structure ◽

Self Consistent ◽

Good Agreement

ABSTRACTThe origin of the Rh polarization at the interface with Fe is discussed within a self-consistent mean-field parameterized tight-binding model. Since experimentally it is not yet known how Rh grows on Fe (001), in this paper we consider both fee and bec growth. When Rh grows in the fee structure, it expands its lattice parameter and a polarization is present up to 3 layers, whereas in the bec case only the Rh atoms at the interface are polarized. The results obtained are compared to recent spin- and angle-resolved photoelectron spectroscopy experiments. Good agreement with experiment is obtained in the case of a fee Rh configuration.

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ON THE COUPLING BETWEEN ELECTRONS AND SOFT-MODE PHONONS IN La2CuO4

Modern Physics Letters B ◽

10.1142/s0217984990000623 ◽

1990 ◽

Vol 04 (07) ◽

pp. 489-496 ◽

Cited By ~ 3

Author(s):

Z. K. PETRU ◽

N. M. PLAKIDA

Keyword(s):

Fermi Energy ◽

Soft Mode ◽

Tight Binding ◽

Electronic Energy ◽

Tight Binding Model ◽

Energy Bands ◽

Phonon Modes ◽

Binding Model ◽

Bond Bending ◽

Electronic Energy Bands

An interaction between soft bond-bending phonon modes and localized 3d – 2p electrons is considered. Its strength is estimated to be of the order of 1 eV/Å. By means of the tight-binding model, the electronic energy bands of La 2 CuO 4 are calculated. It is explicitly shown that a tetragonal to orthorhombic transition does not open a gap at the Fermi energy.

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Tight binding model of conformational disorder effects on the optical absorption spectrum of polythiophenes

Physical Chemistry Chemical Physics ◽

10.1039/c6cp00832a ◽

2016 ◽

Vol 18 (18) ◽

pp. 12521-12533 ◽

Cited By ~ 16

Author(s):

Joel H. Bombile ◽

Michael J. Janik ◽

Scott T. Milner

Keyword(s):

Absorption Spectrum ◽

Optical Absorption ◽

Optical Absorption Spectrum ◽

Tight Binding ◽

Cost Effective ◽

Tight Binding Model ◽

Binding Model ◽

Conformational Disorder ◽

Disorder Effects ◽

Conduction Bands

A cost effective model that effectively reproduces the effect of dihedral rotations on the valence and conduction bands of polythiophenes.

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Two-Gap Superconductivity in MgB2

International Journal of Modern Physics B ◽

10.1142/s0217979203018557 ◽

2003 ◽

Vol 17 (13) ◽

pp. 2589-2598

Author(s):

Angsula Ghosh

Keyword(s):

Critical Temperature ◽

Specific Heat ◽

Temperature Dependence ◽

Order Parameter ◽

Tight Binding ◽

Tight Binding Model ◽

S Wave ◽

Binding Model ◽

Half Filling ◽

Good Agreement

We study the superconductivity in MgB2 using a tight binding model to investigate the doping dependence of the order parameter and the critical temperature. We consider both the anisotropic and the isotropic s-wave pairing to study the coexistence of the two gaps. A good agreement between the existing experiments and our theoretical curves is observed. The temperature dependence of order parameter, specific heat and penetration depth at half filling are also demonstrated and are found to be in accord with the available experimental predictions.

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