Questions tagged [tight-binding]

Questions related to the tight binding method in materials science.

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Tools for working with tight-binding models

I would like to analyze a Slater-Koster tight binding model for some materials. I have the data for both the Hamiltonian as a matrix-valued map on the reciprocal lattice $H_{mn}(\vec{T})$ and the ...
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5 votes
0 answers
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Cheap NMR shift calculations in periodic systems

I am looking for an electronic structure method code (e.g. tight binding DFTB) that supports cheap calculations of NMR shieldings and has support for periodical systems. I would be grateful for any ...
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4 votes
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How to implement a Weyl semimetal in tight binding? [closed]

I want to study electronic and thermal transport properties of a Weyl semimetal. Until now, I have used only the continuum model hamiltonian ($H=k⋅σ$). As the continuum model has several limitations, ...
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8 votes
1 answer
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Which software is suitable for visualizing the electron wavefunctions in a crystal?

I'd like to use the tight-binding model with a linear combination of atomic orbitals. It should show the full energy bands, as well as the spatial probability distribution for each eigenfunction of ...
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9 votes
1 answer
139 views

Evaluating Seebeck coefficient using DFT

I am working with semiconductor materials using the SIESTA DFT package. I have tried the BoltzTraP2 software interface with SIESTA, however the results (Seebeck coefficient of MgO and Si) did not ...
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6 votes
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Constructing the symmetry operator from k.p Hamiltonian [closed]

I have a question regarding to how to construct an operator from k.p Hamiltonian. Maybe there are some problems in my understanding, I hope you can point me out and correct my description if I made ...
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7 votes
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The quantum spin Hall phase with Z2 = 0? [closed]

I used first principle calculations to study the thin film model. An obvious crossing was shown to appear at the gamma point when the edge state was calculated, which was originally predicted to be ...
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11 votes
1 answer
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How to use wavefunctions/density to determine which orbitals lead to edge states?

I have a large matrix for a 1D zigzag edge model of an otherwise $3\times 3$ tight-binding Hamiltonian (3 basis functions, each corresponding to an atomic orbital), involving the variable $k_x$. The ...
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7 votes
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Construct a parity operator at a TRIM point? [closed]

I want to calculate the band parity at some TRIM (time-reversal invariant momentum) point in Brillouin zone. Parity was defined as the eigenvalue of the inversion operator. My question is how to ...
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  • 2,673
9 votes
2 answers
704 views

Data format of wannier90_hr.dat from wannier90

I did a calculation on a bulk system with DFT and fit it with the tight binding matrix with wannier90. There is question on this. I try to write my own code to construct a slab tight binding matrix ...
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10 votes
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Is it possible to construct a tight binding matrix of high atomic layer thin film from the lower one?

Given a tight binding matrix of a thin film system with a few atomic layers, is it possible to construct a tight binding matrix of higher atomic layers thin film from the lower one? For example, I ...
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9 votes
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How to interpret WannierTools Python code that generates tight-binding model in the wannier90_hr.dat format? [closed]

I am getting myself acquainted with Wannier Tools. Wannier Tools requires two inputs, a wt.in file, and a .dat file. This ...
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8 votes
1 answer
180 views

How to calculate the parity of a band at a particular point in Brillouin zone

Some references mentioned that the calculation of $Z_2$ topological invariant of a crystal can be greatly simplified if the crystal contains inversion symmetry. But it involves the calculation of the ...
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6 votes
1 answer
319 views

Calculating the surface state with Wannier tools

Currently I met a problem when I calculate the surface state of a topologically non-trivial thin film system. I did a DFT calculation and fit the result with wannier function. The fitting looks pretty ...
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12 votes
0 answers
145 views

Calculating the Chern number on a 2D surface of a 3D insulator

I want to calculate the Chern number of a surface of 3D time reversal insulator. I know the 3D topological insulator is characterized by the Z2 index annd that the Chern number can be used to ...
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12 votes
0 answers
114 views

Orbital-free DFT and Density Functional Tight-Binding: Comparison [closed]

There are many flavors of DFT that are alternative to, or go beyond the Kohn-Sham formulation (KS-DFT). Some of these are based on approximations that sacrifice accuracy when compared to KS-DFT, but ...
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17 votes
1 answer
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How to understand the time-reversal symmetry in graphene?

A lot of references say that the Dirac cone in graphene is protected by inversion and time-reversal symmetries. How can one understand this statement? How can one show explicitly that the gapless ...
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21 votes
2 answers
718 views

Derivation of Slater-Koster equations

I am trying to derive the Slater-Koster equations (Table. 1 of Ref. 1) for the two-centre approximation of hopping integrals between atomic orbitals. I understand that Slater-Koster approximates the ...
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12 votes
1 answer
276 views

DFT vs tight-binding solutions for a Dirac cone in graphene: Why is the DFT version squeezed?

I'm a beginner at DFT calculations with VASP software. I use it to calculate the band structure of graphene and I obtain the following result: I used it to calculate the band structure of graphene ...
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  • 2,673
17 votes
1 answer
120 views

Benchmark transition state geometries in condensed phases

I'm seeking references/benchmarks for transition state geometries of reactions in condensed phases like crystals, zeolites, or surfaces. Basically the system just needs to be considered big, yet ...
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  • 7,744
16 votes
1 answer
290 views

How to construct a Tight-Binding Hamiltonian from first-principles computations?

Effective Hamiltonian approaches such as the Tight-Binding method played a central role in the reconciliation between chemistry and in physics in the solid state. A classical and complete treatment of ...
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