All Questions
Tagged with terminology crystals
17
questions
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How to call ellipse packing structures?
My research group and I are trying to figure out what is the correct terminology for two different packing structures of 2D ellipses. The two structures are displayed below as Structure A and ...
1
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1
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157
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Can the lattice of an element with face-centered cubic (FCC) crystal structure be regarded as simple cubic (SC)?
According to Introduction to Solid State Physics by C. Kittel,
An ideal crystal is constructed by the infinite repetition of identical groups of atoms. A group is called the basis. The set of ...
- 437
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55
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Difference between Bravais lattice, point lattice and space lattice
I am good at crystallographic terminologies. Can somebody explain to me what is the difference between Bravais lattice, point lattice, and space lattice, if any?
- 11.7k
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62
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Why the primitive unit cell is called primitive?
while reading solid state physics I came about the concept of primitive and non-primitive unit cells and I was wondering about why it is called primitive.
-3
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Why the face centered cubic is called so?
while reading solid state physics I was just wondering why the face centered cubic is named so. is it just because that there are atoms in the center of faces/sides of the unit cell?
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What is $B(N)$ crystal structure? What does this nomenclature stand for
Is it basic cubic with 20 atoms?
I can't find the explanation for this nomenclature online. Maybe I could find it in a textbook, but if someone answers it here, other people can just google it.
- 38
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58
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What is an incommensurable grain boundary?
As the title states, I'm unsure what it means to be a commensurable or incommensurable grain boundary (when discussing dislocations and small angle grain boundaries). I see the term being used ...
- 143
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371
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Crystalline long range order
I am reading an article, in which the phrase "crystalline long-range order" appears. I am not really sure what this phrase means here. I tried to find references online, but there seems to ...
- 508
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2
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Can two atoms be a crystal?
In the physics literature, you can often find the term "two-ion crystal", when talking about two ions that are confined in a e.g. Paul trap. How is this possible? Shouldn't a crystal be a structure ...
- 1,221
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537
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Isn't end-centered monoclinic same as monoclinic?
monoclinic is simply an extruded parallelogram. If we place end centers on parallelogram faces then taking half of both diagonals and same height as before as 3 basis, its the same. That's what I ...
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What does the term "inversion symmetric" mean?
I've read the responses to the question `"Lack of inversion symmetry" in crystal?' but I'm still unsure about the meaning of inversion symmetry. Which of the following two dimensional ...
- 61
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Why is Fourier space called as momentum space?
If I take a periodic wavefunction $\psi\left(\vec{r}\right)$ and then take the Fourier space dispersion of the wave function as defined below
$$
\psi(\vec{k})=\iiint_{-\infty}^{+\infty}\psi\left(\vec{...
- 1,398
11
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What's the difference between a time crystal and a system undergoing periodic motion?
What's the difference between a time crystal and a system undergoing periodic motion? My understanding of a crystal is that it is a rigid body with a spatially periodic structure. Is any system ...
- 22.7k
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The meaning of a 'punctual atom'?
This document refers in the to a 'punctual atom' in the context of neutron diffraction from crystals. I have nether come across this term before. What does it mean and how common is it as a phrase?
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Miller indices vs Laue indices?
I am looking at the difference between the Miller indices and Laue indices in crystal structures. I will denote the former by $hkl$ and the latter by $HKL$.
I understand that $hkl$ must be coprime ...