Questions tagged [lattices]
For questions about systems with a repetitive arrangement of constituents, such as a crystal lattice or Bravais lattice.
14 questions with no upvoted or accepted answers
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What are the limitations of the Born-Lande' equation?
The Born-Lande' equation is used to theoretically calculate the lattice energy, $\Delta U$, of ionic compounds. It is often cited as such in literature,
$$\Delta U = -\frac{k_Az_1z_2Me^2}{4 \pi \...
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How is the Born-Lande equation modified when the structure is not NaCl?
Often the Born-Lande equation is quoted (alongwith the calculation of the Madelung constant and Born exponent) with reference to rock-salt structure. But what if we take some other crystal, like ...
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What is the precise definition of crystal systems and unit cell?
I was just wondering why there wasn't a rhombic 2D Bravais unit cell (wasn't there in the material provided to us) and realised upon drawing that it is the same as a centered rectangular unit cell. ...
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X-ray Diffraction Lattice Spacing
I have crystal structure data which I have indexed. I am able to index the (010) (100) (011) (110) and (111) planes. Is there a straightforward method to calculate the a,b,c lattice constants based ...
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Unit cell in a hexagonal closed pack structure
My textbook says that there are only 14 possible 3D lattices(Bravais Lattices).
One of these 14 lattices is a hexagonal lattice in which only a primitive variation is given to be possible.
But then I ...
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Lattice Energy of MX2 type
While finding the solution to the question that which among BaO and BaCl2 has hi that is energy I found that it was BaO whose lattice energy is high and there were explaining it just with charges. So ...
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Difference in properties of water as ligand vs 'in lattice'
I'm trying to understand the difference in properties between water in crystals in different positions in the lattice. In this wikipedia article It quotes:
Both notations can be combined as for ...
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Packing fractions of HCP and FCC
The packing fractions of hexagonal close packed unit cell and face centred cubic unit cell come out to be same when calculated geometrically.
Is it just a coincidence? Differently put, could it be ...
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Data for Madelung Constants
Where can I find data for the Madelung constants for various ionic compounds? Specifically, I am looking at silicon tetrachloride, yttrium (III) chloride, zirconium (IV) oxynitrate hydrate, niobium (V)...
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Why does malleability and ductility of interstitial carbides decrease?
Why does the malleability and ductility of interstitial carbides decrease? I read the following in my book, but I am not able to find what is the reason for the same. Why does this happen? Is it to do ...
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Unit cell of hcp structure
It is given in my book that the structure in figure-1 is the unit cell of hcp structure.
So why then is the structure in figure-2 not the unit cell as we can repeat the structure in figure-2 to get ...
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What is meant by "rotation about an axis that passes through a lattice point"?
I am currently studying Introduction to Solid State Physics, 8th edition, by Charles Kittel. In the section Fundamental Types of Lattices of chapter 1, the author says the following:
Crystal lattices ...
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Need to normalize lattice enthalpy by no. of nearest-neighbor (NN) interactions to equate to NN interaction strength?
I've seen electrostatic interaction energy (from $E\sim \frac{q_1 q_2}{r}$) used to explain differences in lattice enthalpies between different crystalline solids. For example, I've seen it explained ...
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Why does Cs2SO4 have more lattice energy that Na2SO4?
My chemistry teacher told us that $\ce{NaF}$ has a higher lattice energy than $\ce{CsF}$. He explained it by telling lattice energy is inversely proportional to size of ions added. He then mentioned ...
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