Unanswered Questions
68 questions with no upvoted or accepted answers
2
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How to adapt Einstein summation subscripts from 3-Index to 4-Index tensors in Numpy's einsum?
I am trying to apply frozen core approximation in order to get the effect of the forzen core orbitals on the 1-electron and 2-electron Hamiltonian. According to the notes on Page 28, the electronic ...
2
votes
0
answers
21
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MD calculation of hexagonal boron nitride using LAMMPS
I use LAMMPS to perform MD calculations for hBN. However, I can't find a suitable tersoff potential file. Where can I get it?
- 21
3
votes
0
answers
36
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How to correctly set the high-symmetry point path block when there are breakpoints in the recommended path?
I watched Dr. Mohan's tutorial video, and the settings he provided are as follows:
...
- 31
1
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0
answers
52
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2
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0
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41
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Is it reasonable to extract the Schottky barrier height from the zero-bias transmission spectrum?
The following question is based on discussions What's meaning of zero energy reference point in the energy-axis of zero-bias transmission spectrum extracted by sisl.get_sile('systemlabel.TBT....
- 167
3
votes
0
answers
61
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Which ensemble to use for annealing?
I am trying to do a simulation for solid Mg dopes GaN in LAMMPS where I follow the following procedure:
Energy minimization at 0K
Heating to 873K
Holding at 873K
Quenching to 300K
For this I am ...
2
votes
0
answers
76
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How can I call LAMMPS from a Python script multiple times in paralllel?
I'm working on a Python program that needs to call multiple LAMMPS runs and extract some computes. The code looks something like this:
...
- 166
2
votes
0
answers
32
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How to start a unrestricted hartree fock (UHF) calculation with a custom guess in PySCF?
At first I want to do a UHF calculation of Li$_2$ dimer with spin=6 which shall give a sequence of $\sigma_{1s} \sigma^*_{1s} \sigma_{2s} \pi_{2p_x} \pi_{2p_y} \pi_{2p_z}$ (ordering might be wrong) ...
1
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0
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36
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I want to simulate a material with 3 atom types in LAMMPS, but the LJ parameters aren't available in any source. How can I calculate them?
I am trying to find the thermal conductivity of a material with 3 atoms kinds through the Green-Kubo method. I could find the LJ pair coefficients of the material in any literature or database. I ...
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1
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0
answers
14
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which electrode is better when calculating seeback coefficient of a 2D semiconductor? bulk metal electrodes or semiconductor material itself
I would like to calculate the seeback coefficient of a 2D semiconductor.
I am thinking,
If I use bulk metallic electrodes, the semicondutor itself is not heated because transiesta can only put ...
- 4,394
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7
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Siesta: Is that the advantage of using bulk-like metallic electrodes we can calculate channel materials of arbitrary length?
When we talk about adding extra screening layers to screen charges towards electrodes when we use semiconductors as electrodes,it sounds like the screening layers are not what we expect in our device. ...
- 167
0
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23
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siesta: Why are graphene nanoribbons with finite gaps used as electrodes without needing much more screening layers?
I did know one should use bulk-like metallic electrodes to avoid problems with screening and Fermi-level definition, and if I have to use semiconductors as electrodes, I need extra screening layers in ...
- 167
2
votes
0
answers
41
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siesta: Why is the current 0 for V < 0.8?
I met same problem in this questionsiesta: current-voltage threshold value is not consistent with the band gap value
After I finished this tutorial https://github.com/zerothi/ts-tbt-sisl-tutorial/tree/...
- 167
2
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38
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2
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56
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Obtain Phonon density of using Lammps
I have a need of obtaining the phonon density of states using lammps MD simulations.
could you please explain the approach(s) with the steps involve it?
Thanks
