Newest Questions
4,805 questions
3
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Standing excitons in boron-doped diamond
I am dealing with standing excitons in boron-doped diamond. These excitons arise due to a local disturbance of the dielectric constant in the region of the boron atom. If anyone considered the ...
- 31
1
vote
0
answers
28
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Installing SIESTA using SPACK
I am following the instruction from here to install SIESTA using SPACK.
The command spack repo list, return, as expected:
...
- 24.5k
1
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0
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15
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Optical properties calculation considering vector potential
I’ve been calculating optical properties using Quantum ESPRESSO and Yambo, which include only instantaneous and longitudinal electron-electron interactions (scaler potential). Now, I'm interested in ...
- 1,005
3
votes
1
answer
25
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Are PAO.Basis and PAO.BasisSizes able to be used with the same or different tag in the SIESTA input file?
The system we are working on contains a variety of atom types; for some, PAO.Basis is available on the website, but for others, it is not. As a result, we must use <...
10
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3
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How can we test a code for an algorithm that is implemented for the first time?
I have been implementing a density functional tight binding software from scratch to experiment with it. I based myself off papers describing the theory and two concrete implementations that I could ...
- 353
3
votes
1
answer
49
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Limitations of machine learning in predicting perovskite band gaps?
Perovskite oxides are a class of materials with tunable electronic properties, making them valuable for solar cells, LEDs, semiconductors, and optoelectronic devices. A key property that determines ...
- 131
2
votes
1
answer
103
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Quantum ESPRESSO relaxation not converging (BFGS)
I am performing calculations using QE and I'm having continuous errors with bfgs. I would like to inquire about this as I don't know how to resolve it.
After receiving structures using the API from ...
- 21
5
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37
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Molecular orbital diagram for tetragonally compressed (D4h) octahedra
How can I construct the correct molecular orbital (MO) diagram for an octahedral complex with tetragonal compression (D₄h symmetry), where two oxygen ligands (z-direction, 2.1 Å) and four sulfur ...
- 629
2
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Installation of siesta on apple silicon
I am trying to install siesta 5.2.2 on macbook air with apple silicon chip. But, I am getting errors while installing using cmake.
First I executed ...
- 389
4
votes
1
answer
2k
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What does "200 nanoseconds of simulation" mean?
I have begun studying molecular dynamics, but some concepts still confuse me.
For instance, when I encounter the phrase "The simulation ran for 200 ns," I am puzzled by its meaning. What ...
2
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0
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Symmetry of intermediate compositions in solid solution. Finding lowest energy intermediate compositon
I am trying to find lowest energy structure of (PbxZn1-xS) solid solution, I have built a 2x2x2 ZnS supercell(32 Zn atoms) and one by one replacing Zn atoms with Pb atoms to simulate the random ...
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Convergence issue in quantum espresso code
I am a begginner in quantum espresso.
I have performed vc-relax calculation with this code. But, after calculation stoped the "job done" didn't appear. In following you find the last lines ...
- 171
4
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47
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Choosing high symmetry path for heterostructures
When we model heterostructures or compare bulk and slab structures, how does one proceed to choose the high symmetry k-points path. I have seen papers/articles often choose the same points for ...
- 63
5
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0
answers
102
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Best practices for statistical error estimation in molecular dynamics
I'm performing a molecular dynamics (MD) simulation of a system of particles in a harmonic oscillator, trying to calculate its average kinetic energy. The exact kinetic energy is known from ...
- 51
1
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0
answers
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Which S structure to use for chemical overpotenital
I am calculating formation energies of hetradoped C substrates and the chemical overpotential for S is giving me a headache which reference material should I be using. I am currently going with bulk ...
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