Unanswered Questions
30 questions with no upvoted or accepted answers
3
votes
0
answers
25
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Atomic basin partitioning with electron density grid
I am performing Hirshfeld Atom Refinement (HAR) calculations with XRD data using aspheric atomic scattering factors, which are calculated from wavefunctions optimized in Orca. My crystal structure has ...
3
votes
0
answers
31
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How to model and compute the structure of high entropy alloys (HEAs) using SSOS methods with ATAT
I've recently been working on structural modeling of HEAs and got a little confused when I read about the SSOS approach. I would appreciate it if anyone is familiar with the SSOS method or MCSQS and ...
3
votes
0
answers
50
views
Miller indices and periodic boundary conditions
I want to implement building the Miller indeces in my program Chemcaft. Currently I need to understand more the computations with periodic boundary conditions (PBC) needed for crystallographers.
The ...
- 496
3
votes
0
answers
39
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What is convention of predefined coordination system for defining elastic constant of a specific material
I try to find the elastic constants of LiTaO3 from online databases. I did find a page that lists them https://www.roditi.com/SingleCrystal/Lithium-Tantalate/LiTaO3-Properties.html
As I know, the ...
3
votes
0
answers
53
views
Is it possible to find a cubic supercell for a non-cubic crystal structure?
Suppose that we have a crystal material with a non-cubic unit cell. E.g. $\alpha \neq \beta \neq \gamma \neq 90^{\circ}$. Is it possible to find a supercell such that $\alpha = \beta = \gamma = 90^{\...
- 211
3
votes
0
answers
31
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Is it a good idea to always read charge and orbitals if I am working on similar systems?
For example, if I am investigating of the elastic properties of a crystal by doing a lot of computations of crystals applied with small strain.
Also, is it a good idea to read charge and orbitals when ...
- 461
3
votes
0
answers
84
views
How to generate pole figures from limited amounts of area detector X-ray diffraction from thin films (explain it like I'm five years old)
Historically powder X-ray diffraction was the go-to method for reconstructing crystal structure. X-ray sources were limited in intensity and emittance and so to collect data in a reasonable amount of ...
- 2,074
3
votes
0
answers
449
views
How to transform the conventional cell to primitive cell, by hand?
I am following this tutorial to transform a conventional cell to a primitive cell, but I am not sure how to determine the primitive copy of some atom in the conventional cell.
For example, in the ...
3
votes
0
answers
52
views
How to visualize the basis in the unit cell of crystals?
Usually, the unit-cell of a crystal is made up of lattice points and basis, but all the crystallography software like VESTA doesn't show the basis, is there any ...
- 2,107
2
votes
0
answers
27
views
Surface atoms concentration
I have a bulk crystal that contains 4 different elements. I want to cut the crystal in such a way that the atoms at the surface still obey the concentration of each atom in the bulk. At least close. ...
- 609
2
votes
0
answers
48
views
A problem to simulate the kinetic energy operator using some field going through a crystal
We know about a differentiation and integration operations and also other ones can be simulated by an analog way using electric circuits with operational amplifiers (here are articles of the ...
- 1,027
2
votes
0
answers
40
views
How to rotate Octahdrals locally along with unit cell axis
As the continuation of this discussion d orbitals PDOS analysis, I am curious about crystal field effects on a given atom by analysing $m_l$ projected DOS, the individual d-orbitals are given with ...
- 470
2
votes
0
answers
32
views
Error in 2D Ewald sum for a multipolar expansion
I am attempting to calculate the potential of a particle at the center of an infinite two-dimensional lattice as per the following reference:
Reference: Lambin, PH & Senet, P. Ewald Summation of ...
- 21
2
votes
0
answers
32
views
How to find the scaling factors for minimum image convention?
Suppose that we have an arbitrary (not necessarily cubic) unit cell with cell parameters $\mathbf{a}$, $\mathbf{b}$, $\mathbf{c}$ (lattice vectors) and $\alpha$, $\beta$, $\gamma$ (lattice angles).
We ...
- 211
1
vote
0
answers
69
views
Code to build the monoclinic crystal lattice
Benzoic acid exists as a solid at room temperature. So, I want to build a monoclinic crystal structure of this molecule. Is there any code available to do that? Thanks.
Edit: Is there any way to build ...
- 1,416